Category: Studio Lights Education

Most outstanding children’s portrait photographers today use 35mm digital single-lens reflex cameras (DSLR). Medium format and large format cameras were once the mainstay of the photography industry, but now few people use them because DSLRs are so flexible that they have taken the world by storm.

Lens

When choosing the right focal length of a portrait lens, one principle is that the focal length is twice the diagonal of the camera frame used. For example, when using a camera with a full-frame image sensor (equivalent to a 35mm film format), a 75mm to 85mm lens is usually a good choice.

When the sensor is smaller than 24mm×36mm, the focal lengths of all lenses actually become longer. When using telephoto and telephoto zoom lenses, this is usually not a problem, because the maximum aperture of the lens has not changed, but when using expensive wide-angle or wide-angle zoom lenses on the digital camera body, you will find that the wide-angle is significantly smaller. This will be disappointing. For example, if the focal length factor is 1.5 times, a 17mm lens will “become” a 25mm lens.

Fortunately, camera makers working to make the chip size smaller have begun to introduce lenses designed specifically for digital imaging. With these lenses, the imaging circle (the area where the focused light falls on the focal plane or digital imaging chip) is smaller but more accurate, thus compensating for the smaller chip size. Therefore, the price of the lens is cheaper, the size is smaller, and it can still provide the same large focal length range as traditional lenses.

The 50mm lens is ideal for shooting three-quarters or full-body portraits. Because a good shooting distance can be achieved at this time, the background can be well integrated into the photo. In this photo, the photographer wanted to show the sharpness of the painted walls, so he used the EF 50mm f/2.5 compact macro lens and Canon EOS 5D camera to shoot with an aperture of f/11.

Standard lens

When shooting three-quarters or full-body portraits, it is recommended to use a standard focal length lens (35mm ~ 50mm, depending on the camera’s sensor size, as described above). Due to the height of children, shooting three-quarters or full-length portraits of children requires you to be closer to the subject compared to shooting adult portraits. This “standard” lens can achieve a perspective effect without any distortion when working at this distance.

When shooting children, use a shorter telephoto (here, a 24-70mm zoom lens with 70mm end) can achieve excellent perspective, larger photo size, and a good working distance.

The only problem encountered when using a standard lens is the inability to separate the subject from the background. Generally, it is better to make the background slightly blurred and out of focus, so that the audience’s attention will be focused on the child, and the background will not be overwhelming. When using a standard lens and a lens with a shorter focal length, the depth of field will increase slightly.

Therefore, when a large aperture is used for instant shooting, it may be difficult to separate the subject from the background. This problem is particularly prominent when shooting outdoors, because light spots or other distracting background elements can easily distract attention from the subject (note: fortunately, in the digital age, in the post-processing The background element is very simple).

Shorter telephoto lens

In adult portrait photography, shooting with a shorter telephoto lens can achieve accurate perspective effects. Since children are much shorter than adults, shooting with a shorter telephoto lens can achieve the same effect as using a longer telephoto lens in adult portrait photography. A shorter telephoto lens can achieve a better working distance, which is useful when photographing children. It can achieve a shallow depth of field and usually soften the background.

Longer telephoto lens

If you have a studio, you can use a longer lens. 200mm lenses or very popular, 80-200mm f/2.8 zoom lenses are good portrait lenses because they can achieve a very shallow depth of field, blur the background, and provide a clean background.

The telephoto lens can achieve a very narrow angle of view. When shooting with a large aperture, this focal length can achieve a very shallow depth of field, so it can be used to highlight the eyes or sharply focus on the front of a child.

The 80-200mm zoom lens is very flexible, you can use intermediate focal length settings, such as 105mm or 120mm, which can achieve the correct perspective effect and excellent background control and composition.

The effective focal length of 300mm (using an 80-200mm zoom lens on the Nikon D2X) provides a compact composition and shallow depth of field effect, minimizing background interference.

In most cases, try not to use an extremely telephoto lens above 300mm.

First of all, the perspective effect may be distorted. Various facial features seem to be compressed together. According to the working distance at the time of shooting, the nose usually seems to stick to the child’s face, and the ears seem to be parallel to the eyes. Secondly, when using this kind of lens, it is usually very far away from the child to shoot, so it is difficult to communicate with the subject.

You definitely want to be close enough to your child to have a conversation. But sometimes getting too close can disturb the child. At this point, the assistant can play the role of a “good policeman”, and the telephoto lens can keep you away from this trouble.

In summer, the better outdoor light becomes the biggest obstacle to shooting, because different light directions will cause different degrees of shadows on people’s faces. The stronger the light, the more obvious the shadows, so you need to use reflectors, flashes, and soft boxes. It can be used as a filling light to reduce unsightly shadows and reduce the contrast between people and the background. So in order to obtain a fresh and soft texture portrait, how to add light?

The Role of Supplementary Light

Taking pictures outdoors in full sunlight, most of the time due to the strong light, the contrast formed is large, which can easily cause shadows on the model’s face. In order to deal with the shooting of various outdoor scenes conveniently, it is necessary to learn the fill light skills of flash and reflector to obtain clear and high-quality portraits.

In addition, the proper fill light can also create a catch light and make the characters more energetic.

Correct Lighting Techniques

1. Flash fill light skills

Generally, there are built-in flashes and external flashes. In fact, a small amount of light from the pop-up flash on the camera can drive off the heavy projection on the subject’s face, but the external flash is highly operable.

When using an external flash, avoid aiming the front of the lamp at the model. This will cause the flash to be pointed upwards or use the reflection principle to fill the light.

For professional photographers, the external flash is usually equipped with a lampshade, so that the light will be softer.

The built-in flash can be covered with a layer of paper towel, or with a translucent plastic bag to serve as a soft light effect of the hood.

2. Fill light skills of reflector

In the sun, the reflector can eliminate the shadows on the faces of the characters and increase the light on the eyes. Moreover, the use of reflectors can make the figures in the shadows fuller and more accurate face exposure.

The current reflector has many functions, and different surfaces can be used to absorb light, reflect light, and block light.

Use a hood to avoid the highlights directly above the model

Under the scorching sun, use a reflector to reflect light from top to bottom, retaining the detailed texture of the model’s face.

3. Use soft and reflective surfaces together

Compared with a flash, the reflector is easier to use and has a larger reflective area, making it more suitable for shooting full-length or half-length portraits. With good effect and high cost performance, it can be used by professionals or non-professionals.

 

 Correct Metering Technique

Meter the scene, not the subject.

The person is backlit and the face is dark. When shooting, first meter the ambient light. After the metering is completed, turn on the flash, adjust the flash index and the distance between the flash and the model, so that the model’s face is exposed to normal, and finally the model is The environment is exposed accurately.

To find the best flash effect, you need to adjust left and right to take a few more shots until you get a photo with the most natural light, so that no obvious traces of fill light are visible.

If the scene is underexposed, the colors will be more saturated: after metering the scene, subtract another 0.5 to 1.5 EV compensation.

The Location of the flashing Lights

The side lighting is more three-dimensional than the front: lighting from the side of the main body will be more three-dimensional than from the front. In principle, if there is an angle between the light and the lens (about 45 degrees or more), the light will be three-dimensional. When the light is parallel to the lens (camera flash), the light will be flatter.

Lighting from top to bottom is more natural: if the flash is the main light source, imagine the flash as sunlight, try not to light from bottom to top, but from top to bottom.

Make good use of the M mode of the flash: Don’t be afraid of the M mode. In the field of digital cameras, you can continue to try again if you make a mistake.

By analyzing the light consumption of different weather, we understand the softness and hardness of light. For the analysis of the horizontal angle and vertical height of the sun, we have gained the concept of light position. The interpretation of light ratio and tone sums up the shape of the picture with light. And how much do you know about outdoor lighting?

I think at least I understand what lighting is like in terms of behavior. Photography is largely an art discipline. Like many art disciplines, there is no lack of rational and abstract conceptual definitions. The early and mid-term studies of photography can be proved and logical. I think this is an advantage. Logical and proof-based learning is at least much easier than nuclear physics.

When running out of light outdoors, we discussed that cloudy weather is a good time for portrait photography. Under a certain angle of light position, the ratio of sunlight and sky light (scattered light from clouds) is not too big, and it won’t be as absent as it is on a cloudy day. In this way, considerable picture details can be obtained, and sufficient three-dimensional levels can be retained.

As far as the photographer’s efficiency is concerned, the manpower and material resources of supplementary light are also saved to a large extent. I have said that choosing outdoor lighting is also lighting. In the above example, the skylight and ambient reflected light are similar to reflectors in sunny weather. There is an abstract concept of light from different sources with the same effect-auxiliary light.

In modeling lighting, light is divided into the main light, auxiliary light, background light, contour light, and decorative light according to the status abstract.

The main light is the light source that plays the main role in lighting. It is used to display the basic form of the subject, express the three-dimensional space of the picture and the surface structure of the object. Its main function is to express the direction and nature of the light source, produce obvious shadows and contrasts, and shape the image of characters and scenery. In some literatures, it is called shaping light. Generally speaking, it needs to form a certain contrast between light and dark to highlight the three-dimensional sense and texture, and make the surface of the subject produce light spots and flashes through hard light. But not absolute, soft light can also be used as the main light, it can produce rich midtones, but it is lacking in dramatic modeling.

In most cases, the main light is the brightest light source in the overall lighting scheme, but it is not absolute. For example, when shooting against the light, if you don’t shape the silhouette picture, you need to fill in the light from the front. At this time, the fill light plays a major role in shaping the subject. Fill light can achieve the on-camera tone distribution through different angles. In this type of situation, the brightest light plays the role of contour light, and the position of supplementary light is the main light.

The main light can be collected from nature (the sun, environmental reflections), or it can be artificially created. This is not the focus of the discussion. The problem is how to choose the soft and hard, horizontal angle and vertical height of the main light. The most common and familiar lighting effect people face is outdoor sunlight. In terms of aesthetic experience, the sun is above the side and has obvious directionality (this point has been discussed in detail when analyzing the noon top light). The aesthetic requirements of TV photography are generally not too high. Photographers usually set the main light in front of the upper side of the subject, that is, the position of the camera’s optical axis 30°~45°, to achieve a picture that conforms to the public’s aesthetic taste.

Of course, it is not fixed. According to what we pointed out in the vertical and horizontal angle analysis, changing the conventional main lighting method can obtain a variety of picture shapes. The rule is as follows: the higher the main light, the brighter the upper and lower darker; the greater the angle between the main light and the lens optical axis, the less the bright area, and the stronger the three-dimensional sense of space; the environment has a strong sense of space when backlit, and the subject is trapped in a simple dark area, forming an extreme With a dramatic effect.

The lighting (i.e. lighting) of the screen follows strict steps (except for empiricists). After determining the shape of the main light, it is necessary to evaluate the performance of the bright and dark areas in the screen from the perspective of photography. I have mentioned several times that the dynamic range of the human eye and the camera is very different. The upcoming photographic effect can be observed in the LCD viewfinder of the camera, and the displayed contrast is far greater than the visual recognition of the human eye, and the details of the dark area that the human eye can distinguish will most likely be lost.

In addition, the picture shaped by a single key light is often not perfect. For example, high-level light will directly cause the projection of the bridge of the nose and under the chin. The contrast between the bright and the dark of the projection surpasses the human eye, and sometimes feels stiff. Especially in studio photography, sometimes the light source will leave the subject projection in the screen, and the projection should not be emphasized at all times. In accordance with the lighting sequence, the photographer will intervene with auxiliary light.

Auxiliary light is used to weaken the obvious shadows caused by the main light to increase the level and detail of the picture where the main light is not available, and to reduce the density of the shadows. Hard light should not be used as auxiliary light, which will form high light points at multiple angles of the screen. This does not conform to the law of vision. Instead, use soft scattered light or reflected light with no obvious direction.

Normally, the auxiliary light is located on the other side of the main light corresponding to the camera axis. However, symmetrical treatment is generally not recommended. Especially when the side light is the main light, the use of auxiliary light on the other side will cause the above-mentioned many high light spots and the lighting will be chaotic. The ideal light and dark distribution of the picture should start from the highlight (the closest to the main light) and gradually transition to the darkest area, using the auxiliary light on the other side close to the light position to help achieve it.

If you like the highlights on both sides, the shape of the middle shadow is sandwiched, and it is not harmful to break the conventional lighting.

What needs to be considered more than the position is the luminous intensity of the auxiliary light, which is absolutely not allowed to be stronger than the main light. The brightness of the auxiliary light determines the contrast of the picture. The larger the ratio of the main light, the larger the picture contrast, and vice versa. The picture that does not use auxiliary light at all forms a very hard tone. The light ratio that has been sent before, the final 1:16 picture is subjected to extreme processing, not only does not provide auxiliary light, but also uses black cloth to hang on the main light. On one side, the environmental reflections are completely eliminated, forming a very strong dramatic style.

You can also do the same outdoors. When the subject is a character, keep it close to the dark environment, as mentioned in the previous chapter.

Even in the outdoors, the brightness of the auxiliary light is not so difficult to control. The output power of the lamp body as the auxiliary light can be adjusted in the studio. The outdoor reflector is often used as the auxiliary light. The main and auxiliary light ratio can be adjusted by adjusting the distance between the reflector and the subject.

The main and auxiliary lighting method is the most commonly used lighting scheme in photography. When the picture still needs to consider the relationship between the background and the subject, it is necessary to intervene in the background light. This can only be achieved under artificial lighting.

The types of background light are divided into high, medium, and low-key according to the tone. The high profile uses a light source that is stronger than the main light to illuminate the background, making it overexposed. Low-key does not use the background light and prevents the main and auxiliary light from reaching the background, resulting in serious underexposure. The mid-tone background is to use light for the background routinely, and use a certain angle of soft light to illuminate the background to make it appear obvious light and dark gradients. Under special circumstances, you can also use a light-condenser to create a stage effect on the background.

In order to better highlight the subject, when the indoor shooting background is dark tones, the photographer will creatively shoot a hard and strong light from the back of the subject, outline the contour of the subject, and make the highlights overflow. The light with a very clear irradiation range is called contour light. Outdoors, it is the use of backlighting. At this time, it is used for bright background processing. The intensity of the main light should be darker than the contour light to be prominent. When using contour light, the photographer must pay attention to whether the lens will produce annoying halos due to the light entering. When halos appear, you need to change the shooting angle or use a lens hood.

When it comes to lighting for portrait photography, this is a problem that confuses most beginners in photography. In fact, the key to all this is to identify a person’s personality and facial features, and propose a lighting scheme synchronized with it. However, many photographers have developed a bad habit of applying a fixed pattern to all works, regardless of the subject. But some photographers can do this well because he has a complete shooting system and can create and use varying lighting sequences.

Portrait Lighting System That is Difficult to Form

Of course, many photographers have realized the importance of this problem, but it is difficult to make corresponding improvements, because most photographers have not been exposed to a complete and systematic knowledge system of basic lighting technology. Indeed, mastering good light is a lot like understanding the relationship between aperture and shutter speed. You will not be confused until the moment of “click”, and then every photo becomes a variant of this idea.

In this article we will discuss the most basic portrait lighting system. These foundations are the most important technology and the foundation of all other lighting. After understanding the basic knowledge of these photographic lighting, you can easily illuminate any scene.

What is the Key Light?

The main light source of the subject lighting is usually called the “primary light source” or “key light”. Although additional lights can be added to enhance portraits, key lights are usually performed independently. This is very important for learning portrait lighting, because it means that a person can use only one light at a time. If you decide to add additional lights, all the knowledge learned here still applies.

We will control the light on the surface of the subject and understand it as the distribution of light. However, for a specific light source, the distribution of light can be understood as two characteristics that are easier to manage:

Light size: Control the appearance (hard and soft) of these shadows and highlights.

Light direction: Control the position of the shadows and highlights on the subject (the sense of depth).

Although these features seem simple and controllable, their combination can create a range of different effects. If you don’t understand every kind of light development first, then light can easily become unpredictable.

Light Size: Hard Light and Soft Light

We will start with the size analysis, because this is probably the most common problem that leads to poor portrait lighting. When photographers use the term “hard or soft” to describe light, or the term “quality of light”, they actually refer to the size of the light source. Here we first ask for the difference between “soft and hard” light.

Hard light:

Hard light casts strong shadows. In other words, the resulting shadows will have “harder” edges, with fewer transitions between lighting and shadows. If you want to create a moody, irritable, or contrasting scene, then bright lights may be what you want.

Soft light:

Soft light is what we usually call “soft light”. The light tends to “surround” the subject, casting diffuse shadows with soft edges. Soft light is the most flattering type of light in portrait photography. Hard light will highlight the blemishes and textures of the skin, and soft light can help smooth the problematic skin in the photo.

The “soft and hard” of the light will have an essential change in the shooting effect of portraits, and portraits usually benefit from soft light. In order to understand the relationship between them more clearly, we will use Nikola Dechev for 3D simulation to see how they affect the appearance of portraits.

Light Size Change Effect

Note that light sources that are “larger” and “smaller” relative to the subject will produce “soft light” and “hard light”, respectively, because they have different edge effects for rendering shadows and highlights.

A light source larger than the subject can directly hit the subject with more angles of light. Therefore, any specific area can receive a certain amount of direct light, resulting in softer shadows.

Compared to the light source with a smaller subject, a specific area can usually receive all or no direct light, resulting in deeper shadows and stronger contrast.

Distance and Light Size

At this point, we may be slightly misled. The size we have been mentioning in the article before is not the physical size of the light source, but its size relative to the subject.

In the case of the same light source, the closer the light source is to the subject, the softer the light will become. Because this is equivalent to the relative size, we have magnified the light source and changed the distance so that the light illuminates the subject from a wider angle. Similarly, the situation is just the opposite. Although the sun is physically huge, direct sunlight is still hard. Because the sun is too far away, it is still a small light source relative to the subject.

The “Soft and Hard Light” in Portraits

As we mentioned before, the light size not only controls the changes in shadows, it also determines the visibility of fine-scale textures. Pores, blemishes, wrinkles and other facial details will become more visible due to bright light.

In actual shooting, zoom in the light source to obtain soft light techniques:

Diffuser: Place a larger translucent object between the main body and the light source. It can be a diffuser or a white curtain on an open window, which can directly receive light and transform it into a larger light source.

Reflector: By placing different positions, the subject can only receive the reflected light from the reflector, which is equivalent to transforming the reflector into a variable key light. The size and distance of the reflector will determine the quality of light. It is the same principle to aim the flash at a nearby wall or ceiling to live a soft light.

In either case, be careful, because you will end up with much less light.

The direction of light: depth and characteristic expression

Choosing the correct light source direction requires the photographer to strike a balance between several potential competing factors. Usually, this includes depicting a sense of depth and depicting facial features.

Direction and depth:

Creating a sense of depth is a key requirement for portrait photography. However, unless the light illuminates our subject from the correct direction, it is difficult for us to have the correct perception of depth. For example, when we look at a sphere that is similar to the shape of the head, it will only show a three-dimensional effect when light is emitted from the top. Because only a wide range of lighting angles can be used to achieve the above-mentioned sense of depth.

The performance of facial features:

In addition to the head as a whole, it produces the desired sense of depth. Each facial feature also has its own shadows and highlights, and all these features also deserve special consideration. This may require us to avoid casting long shadows to make the nose look bigger, or to draw shadows under the eyes, causing the subject to appear tired. If it is not carefully positioned, our lighting may cause more adverse effects. In order to better understand the depth of light and the expression of facial features, we will learn about several common lighting modes below.

Portrait lighting setting 1: Butterfly light

Butterfly light (also called Paramount Illumination) is named after the butterfly-shaped shadow formed under the nose. Place the key light behind the camera and point it slightly at the subject.

The butterfly light creates shadows around the chin, nose, and cheeks. It can create more eye-catching shadows under the cheekbones. The higher you place the key light behind you or above the subject, the longer the shadow will be projected under the nose and chin. This is very pleasing to most people.

Portrait lighting setting 2: Ring light

By placing the light on a 45º axis slightly above the eye level of the subject. This will move the shadow of the nose to the side of the face. You will get a small ring instead of a butterfly-shaped shadow.

The ring light has a prolonged effect on the face, making the face look thinner, and is often used for head shots. The ring light can be set on either side, and the shadow appears on the opposite side of the light source. The size of the shadow depends on the position of the light and the degree to which the nose blocks the light.

Portrait lighting setting 3: Rembrandt light

Rembrandt light is very similar to ring light. However, the shadow of the nose in Rembrandt is long enough to connect with the shadow on the cheeks to form a triangular highlight on the cheeks.

The lighting is basically the same as the ring light, but you need to continue to position the light to the side until the nose shadow and the cheek shadow touch. This light style looks more dramatic, avant-garde and artistic.

Portrait lighting setting 4: split (or side) light

With split light (also called side lighting), half of the subject’s face is illuminated while the other half is left in shadow. Place the key light on the side of the model at a 90º angle. You can leave the far side completely in the shadows, or use reflective reflectors or fill lights to show more details.

This kind of lighting will highlight the texture of the subject’s face, creating a unique and dramatic effect that is not as common as its lighting method.

Portrait lighting setting 5: wide light

Broad light is a technology that can usually be combined with the above-mentioned lighting modes to solve specific problems.

Adjust the position of the subject so that the part of their face that receives the most light is also the part closest to the camera. This means that your subject needs to maintain a certain angle with you. This is very suitable for people who wear glasses, because wide light is the fastest way to keep the glasses outside the angle of reflection and illuminate the subject. For this reason, school portrait photos and company ID photos usually use wide light illumination. However, it will make the face look wider than usual.

Portrait lighting setting 6: narrow light

Narrow light is the opposite of wide light, and the illuminated face is also the farthest part from the camera. Your subject is still at an angle to the camera, but the light is now on the far side of the face.

Depending on the angle of use, narrow light can perceive facial features well. Narrow light will make the face look thinner, which is in line with most people’s aesthetics.

Understand the second light source: fill light

The second light source is usually our fill light. It can greatly improve portrait lighting, reduce the depth of shadows, and soften facial features. Most importantly, fill light is easy to create, usually a simple fill light or reflector is sufficient. But we need to know how to control the position and intensity of the fill light to produce the desired portrait appearance.

For a single light source, the most important considerations are its orientation and apparent size. Although these have the same effect as the second light source, they usually do not change independently of the main light source. On the contrary, what is usually adjusted is the relative brightness of the fill light to the main light. This controls the intensity of the secondary light source “filling in” the shadow from the main light, which is why the secondary light is often referred to as the filling light.

Fill light ratio:

The term “fill ratio” describes the relative amount of light from the primary and secondary light sources, and effectively determines the overall contrast. For example, a value of 1:4 means that the fill light is a quarter of the intensity of the main light, and a larger ratio produces weaker shadows.

When the ratio is close to 1:2, the effect is usually better. This is enough to produce subtle shadows, but not too strong, and will not completely eliminate shadows (so as to eliminate facial features of the subject).

However, people should always be wary of the seemingly strict rules in photography. Less fill light is usually used for dark “low-key” style portraits with well-defined shadows. More fill light to present a brighter “high-key” style, or just to provide a softer look (such as shooting with a baby). Usually the ratio of 1:2 is an intermediate point.

Position of fill light:

Unlike the main light source, the easiest place for the fill light is to be close to the top of the camera’s axis, but not too close to avoid appearing in the image. Any shadows cast by the fill light on the axis are not visible, so it doesn’t matter if they look difficult (due to the small source).

However, off-axis filling also has its own shortcomings, the worst may be the appearance of fill light shadows. If these shadows are not soft enough, it will result in double shadows that look unrealistic. To counteract this effect, the farther the fill light is from the camera’s line of sight, the larger the light source needs to be.

We focus more on scenes where natural light is the main light source, and fill lights or reflectors are used as secondary light sources. However, it can be easily reversed under certain circumstances. Because natural light is sometimes soft light, such as from a cloudy day or a subject in shadow. What people usually need is a main light source in order to produce the best results.

Light height

The height of the light refers to the height of the person being photographed by the light. The height of the light is different, the effect of shining on the image of the subject is also different. According to the height of the light, it can be divided into top light, overhead light, flat light and upward light.

Top shot light:

When the light is irradiated from top to bottom at the 70-90 degree top light on the top of the subject, it is called “top shot light”. The overhead light is like the sunlight at noon. It will produce bright areas of high light on the top of the subject’s head, nose, shoulders, etc., and will produce bright areas under the subject’s frontal bone, under the bridge of the nose, under the lips, and under the neck Shadows are easy to produce the effect of “monkey face”. Therefore, top light is generally not suitable for facial modeling light in portrait photography. When the character looks upwards, shoots the subject of looking into the distance, eager to pursue, etc., the appropriate top light illumination can also achieve the effect of both form and spirit.

Top light illumination

In the creation of portrait photography, it can also be used as a special effect light. For example, when the height of the top light position does not exceed the main light of the person’s face, it can better express the sense of firmness of the person’s hair and help the three-dimensional response of the vertical image of the picture. For example, when shooting a dancer who is lying prone on the ground, the top light is irradiated to produce the effect of chasing light on the stage, which helps to highlight the theme of the dance appreciation in the picture.

Overhead light

The light is at a low light position 45-60 degrees higher than the person being photographed, and it shines from the top to the bottom, which is called the low light. The overhead light is generally used as the main light source for photographing people. The reason why the overhead light is widely used as the main light source of the picture modeling is because the illumination of the overhead light is more in line with people’s visual habits in daily life. At the same time, the overhead light level, from top to bottom, will produce vertical changes in the light and shade of the subject’s face and body, which is conducive to the expression of the subject’s facial texture and the prominence of the subject’s main image.

When the subject is facing forward, the overhead light will produce shadows under the frontal bones, eyes, bridge of the nose, and chin of the subject’s face. At this time, we can combine the forward inclination of the subject’s posture to effectively compensate for the shortcomings of the subject’s fatness, and use the overhead light as the main light position. Generally, it should also be equipped with lights or reflectors illuminated by a smooth light position as an auxiliary light source to adjust or compensate for the shadow or projection caused by the main light source.

Flat light

When the light is shot at about 0-15 at the same height as the subject, it is called flat light.

The light is irradiated in the flat light position, and will not produce vertical shadows on the subject’s face. In the creation of portrait photography, flat light is used as an auxiliary light source to compensate for the shadows of the subject’s face and other parts illuminated by the main light, and to adjust the natural transition of light and dark contrasts caused by the main light’s illumination of the subject’s face and other parts .

In addition, flat light irradiation is mostly used for photography of children and young girls to express plain and elegant pictures, with crisp and bright tones, to make up for slightly wrinkled skin. For subjects with thin faces, flat light can be used to make up for the defects. For subjects with rough facial skin, flat light can be used to make facial skin more delicate and smooth. At the same time, irradiating with flat light will produce a light spot in the eyes of the subject, which can make the dark eyes of the subject appear bright and full of spirit. Generally speaking, it is better to have a small bright spot on the upper middle of the eyeball. If multiple spots of light appear on the eyeball, it will not only give people a cluttered feeling. It is also not conducive to the expression of the eyes as a “window of the soul”.

Upside light

When the light is from -46 to -10 degrees lower than the height of the person being photographed, it shines from top to bottom, which is called “upside light”.

The illumination of the upward beam will produce a bright and dark light and shadow effect on the face of the person being photographed, so the upward beam can also be referred to as the “bottom light” effect. It is just like the person being photographed is on the beach or on the deck of a ship, and is irradiated by the sun, which intersects with the reflected light on the beach or sea. Therefore, the upward beam does not conform to the common visual habits of people. Generally, the upward beam is rarely used in portrait photography, unless it is necessary to show some evil people who are not right in their minds, and are insidious and cunning. Of course, upside light is not useless. In the current commercial portrait photography, in order to pursue a delicate and white skin effect, eliminate wrinkles on the subject’s face, and express fashionable and alternative character personality, upside light can be used.

When shooting a personal photo with the upside light, two lights with soft boxes are generally used together, that is, one light is above the head of the subject, and the downward light is illuminated, and the other light is on the subject’s head. The illumination from the bottom of the face to the upwards of the upward beam forms an up-and-down echoing light beam to ensure uniform illumination of the subject’s hair, face, neck, chest, arms and other parts, and the illumination effect of uniform brightness.

When shooting commercial portraits such as portraits with upside light, you should pay attention to the following three aspects:

1. The brightness of the upper and lower two lights used is basically the same to avoid the problem of the subject’s face being bright up and down or bright up and down during shooting.
2. Place the upside light as far as possible in front of the person’s face line of sight, and keep it consistent with the person’s face direction, so that the person’s face is surrounded by the upside light, resulting in a bright center of the face and two cheeks Dark lighting effect.
3. Try to keep the upside light in balance with the face of the subject. For example, when the bottom light is shining from bottom to upward at -45 degrees, the posture of the person being photographed should lean forward slightly. Keeping balance with the upward-facing light can not only make the person’s face and other skin parts produce a smooth and smooth light and shadow effect, but also avoid the distortion and distortion caused by the upward-looking light. At the same time, the parallel light can also produce bright eyes in the eyes of the subject.

 Basis for the use of light 2

In front of the floor-to-ceiling windows in the room, with transparent screens as a foil, and natural light coming in from outside the window as the basis for exposure, you can capture the genre of the person being photographed in front of the window talking about love and reading a book and watering flowers. In the studio, strong lights are used to illuminate the light background, so that the subject is in the backlight of the bright background, and the full-side posture can be used to produce a sharp and prominent silhouette of clothing.

The nature of light irradiation

The shape of the luminous body is not good, and the light properties produced are not good. For example, outdoor sunlight produces a bright direct light effect. When clouds cover the sun and cloudy sky, the shape of the luminous body changes from a point light source to a large-area luminous body. What it produces is a soft scattered light effect of light and shadow.

Scattered light

The light illuminates the characters in the form of scattering, which can produce a uniform, soft and coordinated illumination effect. The flash light is to let the light shine on the white ceiling, reflect on the object such as the reflector and then reflect on the image of the person being photographed, or add a reflector or soft umbrella to the film and television lamps and irradiate it, and you can get the flash light. effect.

Scattering refers to luminous bodies, which are mostly used as auxiliary light sources. Compared with the soft scattered light, it adjusts the light and dark transition of light and shadow, and makes up for the lack of light in the dark parts. The scattering luminous body can also be used for large-scale group photos. Multiple lights can be irradiated on the white ceiling, and you can get the good effect of uniform lighting up, down, left and right, and the front and back projections disappear.

Convergent light

The most widely used in portrait photography is the transmission type luminous body. When the light illuminates the subject through the floodlight, it can obtain the accurate direction of the light, the change of light and darkness, the vivid image of the picture, and the undulating artistic effect. Most of them are used as the main light source for character modeling. According to the light irradiation distance from the light irradiation height, the light irradiation direction can change the main light and auxiliary light and other lighting effects.

 

Condensed light

Condensed light is also called hard light. The light illuminates the subject through the condensed form, which can achieve vivid changes in light and shadow, and the effect of sharp and clear projection. Convergent luminous body, if used in the illumination of background light, can produce the effect of clear projected image and colorful and saturated color. If used in backlighting, the effect of beautiful contour lines can be obtained. If applied to the main light source, it can produce an artistic effect with a distinctive theme and strong tonal changes.

Principle of using light

The principle of using light for portrait wedding photography is one main light, multiple secondary lights, one projection, light ratio, light level, and light quality.

1. a key light

The so-called one main light, that is, whether it is outdoor natural light or indoor lighting, it should follow the principle of one sun. A main light is good for shaping the image of a person. According to the brightness of the part irradiated by the main light, a natural and excessively diffuse auxiliary light can be used to form a character image with rich layers and strong three-dimensional impression. A key light is conducive to forming the visual center of the picture. The bright part of the subject illuminated by the main light will first attract people’s attention in the picture and become the center of interest in the picture.

If there are multiple main lights in a picture, not only will the subject be illuminated by multiple main lights, it will produce messy head shadows and light spots, destroying the performance of the perfect image of the subject, and it will also be caused by multiple main lights. The picture without the main light is chaotic.

2. Sub-light

The so-called multiple side lights, that is, the portrait wedding photography screen is to achieve the main body prominent, rich layers and other artistic effects. Under the premise of a main light irradiating, using the negative and secondary light illuminating the painting part can make the light and shadow from the light-receiving surface to the dark side of the light, smooth and thick, and have a good effect of transitioning to a rich natural level. The auxiliary light of the sun can not only make the transition between light and dark naturally, but also double as the eye light, so that a small, congratulatory, bright eye light appears in the photographed person’s dark and transparent eyes, making the photographed person look radiant and piercing.

As one of the sub-lights, the background light can not only remove or weaken the main light, the shadow and the sub-light of the person being photographed, and the projection on the background. The background is relatively calm, and it can also be used in the background. Against the background of light, it enhances the sense of space and three-dimensional depth of the subject in the picture, which is more conducive to the expression of the atmosphere of the picture. For example, a gradual background light with light and dark on the bottom can set off the effect of midtones. In addition, the light and light background light can also create a light and bright high-key effect. Similarly, the contour light is also a secondary light, which outlines the outline of the figure in the same direction as the back side to show the three-dimensional space of the picture and the graceful and natural outline of the subject. As a secondary light, there are headlights that express the details and depth of the hair, and footlights that match the main light when shooting full-length images.

Note: Any auxiliary light cannot exceed the main light

3. A projection

That is, in portrait photography, only the projection of the main light is allowed to illuminate the subject’s negative and secondary light, which can only play a natural transition, enrich the level, and weaken the main light projection, but cannot produce additional projections. Therefore, the positive side light and the negative side light are mostly on the left and right of the camera lens, and the subject is photographed with a smooth light position with a brightness weaker than that of the main light.

As for the background light, contour light, head light, and foot light, they generally assume that the brightness of the main light does not exceed the brightness of the main light, and each plays the role of auxiliary light in conjunction with the main light. To achieve one main light, multiple secondary lights, and one projection, a seamless picture effect must be achieved. Only when the light ratio, light position, and light quality are changed, the space between the primary and secondary front and back will sometimes be darkened.

4. Changes in light ratio

The ratio of the main light to the auxiliary light is called the light ratio. The change in light ratio generally refers to the difference in the brightness of the light shining on the subject’s face, body, clothing, and background. For example, the brightness of 4 on the face of the photographed person can better display the light and dark fluctuations and the sense of level of the face.

Similarly, if the brightness of the background light illuminating the characters to illuminate the background is 1, then a three-dimensional space can be created, but a harmonious atmosphere of the picture can be created. Therefore, in portrait photography, the light ratio is not only the difference in the brightness of the main light and the secondary light of a subject’s face, but also the study of the person and the background, the face and the body, the face and the hands, the face and the hair, and the double The light ratio between each person in a group photo and a group photo.

5. Light level changes

The light position change refers to the changes in the overall position of the light source such as the background of the person being photographed, the pitch, the forward, and the reverse. Except for children and girls and high-profile pictures, the main light for photographing the subject is generally closer to the front side and the lower side.

The sun light that illuminates the person being photographed generally adopts a weaker smooth light position, and the light is taken close to the left and right positions of the camera.

The background light is generally behind the subject, and the background light is illuminated from the bottom up.

The contour light is generally slightly lower than the height of the main light on the back side of the subject, and illuminates the edge contour of the subject on the downside or downside light position.

The headlight is generally on the top of the subject’s head, slightly lower than the height of the main light, and at the position of the top light from top to bottom, illuminates the subject’s hair.

The foot light generally has the same brightness as the main light, or slightly lower than the main light. Below the main light, the legs and feet of the subject are illuminated at a downward angle.

6. Changes in light quality

It refers to the changes in the nature of light irradiation such as hard light, soft light, or direct light reflected light. In portrait photography, the negative and positive light that illuminates a person are mostly soft light or reflected light.

The basis for using light

The use of light must be based on the age, gender, personality, occupation and other characteristics of the person being photographed. Since the characteristics of the subjects are different, the pursuit of light in photography should also vary from person to person. Should try to avoid one-sided, one-size-fits-all light exposure.

1. Appearance: such as a fat round shape, irradiated with downward light with a slightly larger light ratio to form a delicate and dignified face. The slender face can be irradiated with flat side light, with a slightly smaller light ratio to deepen the plump and even effect of the face.
2. Age: If photographing infants and young children, use soft scattered light to show their innocence, liveliness, tenderness and so on. The performance of middle-aged and elderly people can be illuminated with slightly stronger or direct light to show that they are stable, sophisticated, and experienced.
3. Gender: For example, girls should be irradiated with light with soft light and low light ratio to reflect the characteristics of their delicate skin. For shooting boys, it is advisable to illuminate with strong light and obvious light ratio to show their rugged, strong and strong characteristics.
4. Personality: Like the introverted and quiet subjects, Yi Cai uses smooth light with natural transition and harmonious light and shadow to express their subtle and elegant personality characteristics. The shot characters with lively and cheerful personality can be illuminated with bright and dark, undulating side backlighting to reproduce their straightforward personality.
5. Occupation: For the performance of doctors, teachers and other intellectuals, fresh and clear light and shadow can be used to show the professional characteristics of their white angels or human soul engineers. While shooting the images of workers, peasant soldiers and other characters, you can use bright-paced light and shadow processing to highlight their professional characteristics such as creating wealth, changing the world, or defending the country.

Only according to the individual characteristics of the subjects, and the use of light changes to perform illumination imaging from person to person, can each person be photographed vividly, vividly, and achieve an artistic effect that resembles and is beautiful to the person.

If you do not distinguish between face characteristics, personality characteristics of men and women, young and old, and occupational differences, blindly adopting a fixed pattern of light irradiation or excessively decorating and beautifying the characters with large flat lights, and the method of using light that loses the character’s own face and personality is not advisable. In the same way, regardless of whether the image of the character is appropriate, the use of singular decorative lights is often self-defeating and counterproductive.

Intensity of light

1. The power of the luminous body (200 400 600 800 1000)
2. Also depends on the shape of the luminous body
3. Depends on the distance of the light

Understand and hold the intensity of light, you can adjust the brightness of light to form the light and dark changes of light, and produce vivid three-dimensional feeling, rich layering and delicate skin feeling.

Lens

Lens diameter:

The size of the physical aperture of the lens will have a great impact on the image quality. The larger the physical aperture, the greater the brightness, and theoretically, the better the imaging quality of the lens. But at the same time, a lens with a larger caliber is larger in size and weight. In order to facilitate photographers to install filters, the calibers of hundreds of SLR lenses have been unified into several common specifications: 58mm, 62, 72, 77, 82mm. Among them, 77mm is the common caliber of professional zoom lenses. Therefore, it is a common practice for professional photographers to unify one’s own lens caliber and equip multiple lenses with a set of universal filters.

Closest focusing distance and magnification:

The closest focusing distance refers to the minimum distance at which the lens can focus and image clearly. When the shooting distance is less than this value, the camera cannot focus. The calculation of the closest focus distance is the distance from the photosensitive element to the subject, rather than starting from the front end of the lens as generally believed.

The magnification of the lens refers to the ratio of the actual size of the image on the sensor to the actual size. For example, Canon’s 50mm fixed focus has a maximum magnification of 0.15 times, which means that a 10cm-sized object is at its “closest focus distance” (0.45 m), it will be a 1.5cm image on the sensor. Another example is Canon Xinbaiwei, whose maximum magnification is 1x, which means that at the closest focusing distance (0.3m) of Xinbaiwei, the actual object will become an equal-sized image on the sensor. The greater the magnification, the stronger the macro shooting capability of the lens.

Fixed focus lens and zoom lens:

→Prime lens, as the name implies, is a fixed focal length lens that cannot be zoomed. Very commonly used in documentary photography. The main varieties are 20mm, 24, 28, 35, 50mm focal lengths. In the film age, the 35mm lens is most commonly used. This focal length is slightly wider than the normal viewing angle of the human eye.

Compared with a zoom lens, the biggest advantage of a fixed focus lens is its excellent image quality. The imaging quality of a fixed focal length lens is generally better than that of a zoom lens of the same focal length. In addition, the fixed focus lens has a simple structure, a large aperture, a lower failure rate, and a lighter volume and weight. However, fixed-focus lenses are not as convenient as zoom lenses. In the digital age, the usage rate of fixed-focus lenses has dropped a lot.

→Almost all zoom telephoto lenses have better imaging at the short focal end than at the telephoto end, even professional-grade ones. The telephoto section is easily affected by dispersion, which reduces the resolution of the picture.

Due to the insurmountable optical characteristics, the distortion and vignetting of the zoom lens are more serious than the fixed focus lens.

In addition to the highly versatile zoom lens, there are 3 types of lens products in the fixed focus lens that are more suitable for shooting portraits.

①Standard lens: According to optical principles, the design of standard lens is the easiest to achieve excellent image quality. The maximum aperture of the standard lens reaches F1.0.

②85mm lens: This is a lens product specially designed for portrait photography.

③Macro lens: The macro lens combines the shooting functions of macro photography and portrait photography. Compared with the above two lenses, the aperture is slightly smaller. Macro lenses are mostly fixed-focus lenses, which have a very short “closest focusing distance” and 1:1 magnification.

Using a telephoto lens with a focal length of more than 135mm to shoot portraits, you can get an unparalleled background blur effect. The characters and the background will be clearly distinguished. Some people like this effect, but others think that the blur is excessive.

Constant and non-constant aperture:

The fixed focus lens only has a single maximum aperture setting. There are two types of zoom lenses: ① One has a non-constant maximum aperture setting that can vary with the focal length, that is, its maximum aperture will decrease as the focal length increases. ②The other is a product with a constant maximum aperture at all focal lengths.

Anti-shake technology:

Anti-shake technology is divided into two camps, Canon and Nikon use “optical anti-shake”, and Sony uses “photosensitive element anti-shake.” The optical image stabilization device (detected by a gyroscope) is configured on the lens, which increases the cost of the lens, but the actual effect is better. The image stabilization of the photosensitive element is integrated in the body, and the cost is lower, and it can realize the stabilization function with any lens.

Lens focal length and equivalent focal length (correspondence between focal length and angle of view):

Angle of view refers to the angle of the frame range that the lens can capture. When the focal length of the lens is shorter, the angle of view covered by the lens is larger and the picture is wider. When the focal length of the lens is long, the shooting angle of the lens is gradually reduced, and the captured image becomes narrower.

The area of the photosensitive element of the popular APS-C format is smaller than that of 35mm film. Therefore, when shooting with the same lens, the photosensitive element of the APS-C frame can only receive a narrower picture range than the full frame. Conversely speaking, the subject of the photo taken by the APS-C format occupies a larger area of the entire photo frame, and its effect is equivalent to that of a full frame with a longer focal length lens. Therefore, when using an APS-C frame with a traditional lens, you need to multiply the focal length of the lens by about 1.5 times to get the effect of the focal length equivalent to that of the full frame. This is the concept of “equivalent focal length”.

The equivalent focal length is only the equivalent in the angle of view. In the case of the same shooting distance, when shooting with the APS frame and full frame with the same lens, only the angle of view changes. Other factors such as the depth of field and perspective produced by the lens are unchanged.

Because the focal length of the APS frame needs to be multiplied by a conversion factor, it can achieve a telephoto effect with a relatively short focal length.

Focal length

Ultra wide-angle lens:

The equivalent focal length is less than the field of view of 24mm. The picture effect at this time is very open, but at the same time it is accompanied by more serious perspective distortion.

Wide-angle lens:

The equivalent focal length is between 24-40mm. The common focal lengths are 24mm, 28mm, and 35mm. It is a focal length commonly used in daily photography, and on the APS frame, it is close to the field of view of a full-frame standard lens.

Standard lens:

The standard lens is a lens with an angle of view close to that of the human eye on the 135 full frame, and the focal length is between 40-60mm. The standard lens has a simple structure, a large aperture and a low price.

Medium focal lens:

The equivalent focal length is between 60-150mm. The medium focal length lens has soft background blur ability and moderate perspective performance, which is very suitable for shooting half-length and close-up portraits.

Telephoto lens:

The equivalent focal length is more than 150mm. The telephoto lens can make people and scenery in the distance vivid (like a telescope), so it is widely used in ecology, sports, landscape and other photography.

Super telephoto lens:

The equivalent focal length is above 300mm.

In short, the telephoto shoots the local and close-ups; the wide-angle shoots the overall situation and momentum.

The ultra-wide-angle lens can accommodate a wider field of view. However, many beginners will also find that the photos taken with such a lens are very hollow, often large areas of sky and open space, and the beautiful scenery seen at that time is only a little bit in the picture. The telephoto lens can cut the picture and find the wonderful part in the ordinary environment. The ultra-wide-angle lens also frames in some things that should have been removed from the screen, but weakens the subject. When shooting large scenes, the farther scenery will also appear smaller because of the exaggerated perspective of the near and far. The ultra-wide-angle lens strengthens the near and far. If there is no object in the foreground, the picture is naturally hollow.

Lens	Ultra wide angle	Wide angle	Standard (naked eye)	Middle coke	Telephoto	Super telephoto
Equivalent focal length	<24 mm	24-40mm	40-60 mm	60-150 mm	>150 mm	> 300 mm

We can find that the focal length is close to the range of 50mm, which is the closest to what we can see with the naked eye. Many SLR camera kit lenses cover this focal length range. Such as 18-55, 18-105, 18-135 and so on.

→Wide angle:

The shorter the focal length of the lens, the stronger the sense of space and the “perspective”. Perspective is “near big and far small”. This kind of perspective relationship looks closest to what the human eye sees in a lens with an “equivalent focal length” of about 50mm. In the ultra-wide angle, the perspective relationship becomes exaggerated, that is, the closer is larger and the far smaller.

→Mid-focus (85-135mm focal length, APS-C format 50-80mm) lens, is the most versatile portrait photography lens. The medium-focus lens will not cause sudden perspective distortion. The medium-focus fixed-focus lens has the best imaging quality and practical large aperture of all lens products. Large aperture and shallow depth of field are most common in portrait photography.

→Telephoto:

In the telephoto lens, the perspective relationship is weakened, and the distances and sizes are not so obvious, that is, they become “flattened”. Compressed perspective can be said to be the biggest feature of long focal length lenses. In layman’s terms, an object that is actually far away will appear very close after shooting with a telephoto.

Therefore, if you capture a portrait of a person from a distance, the three-dimensional sense of the face will be weakened. If you want to take a close-up of the face with a strong sense of three-dimensional, it is best to get as close as possible to the subject.

Aperture Priority” and “Shutter Priority”

In order to obtain a more convenient operation, there is an “aperture priority” exposure method.

→Aperture priority:

It’s up to you to set the aperture value yourself, and then the camera will give a corresponding shutter value to suit you.

→Shutter priority:

If you want to control the shutter speed personally, you can use the “shutter priority” exposure mode, let the camera give you the corresponding aperture value to match you to get the appropriate exposure.

To control the error of aperture priority and shutter priority, “exposure compensation” is needed.

On digital SLRs, exposure compensation is generally set from -2 to +2. Some cameras even have exposure compensation ranging from -5 to +5. There are 4 levels of exposure compensation from -2 to +2, and each level represents one level of exposure. Simply put, it means a first-level aperture or a first-level shutter. When you use the “aperture priority” shooting mode, you set the aperture value, the camera will give the shutter value, then adjust the exposure compensation, the aperture value will not change, only the corresponding level of the shutter value is compensated.

For example, if you set the aperture F5.6, the camera gives a shutter of 1/250 second, and you adjust the exposure compensation by +1, the aperture is not affected, and the shutter speed will become 1/125 second.

Similarly, in the case of “shutter priority”, if you set the shutter to 1/30 second, the camera will give an aperture value of F8. If you set the exposure compensation to -2, the shutter will not be affected and the aperture value will be reduced to F16.

Focus

There are two reasons for the blurry photos: ①The shutter speed is too slow and the hands are shaking. ②The focus is not aligned.

Autofocus SLR cameras often have multiple focus points. When buying a camera, some friends think that the camera has the same focus points, and they think that their focusing ability is the same, and some people think that the more focus points the better, that is a big mistake. The type of focus point is more important.

“Straight-line” focus sensor:

Sensitive to vertical lines.

“Cross type” focus sensor:

Sensitive to both horizontal and vertical.

“M-shaped” focus sensor:

On the basis of the cross shape, it is also sensitive to diagonal lines, and of course it is more accurate and faster.

Among all the focus points, the “center” focus point is the most accurate and the focusing speed is the fastest. Therefore, many cameras are equipped with a cross or even a rice-shaped focus sensor in the center focus point.

Some high-end cameras also use high-precision “cross-type” focus sensors at other focus points. such as,

The high-end Canon 7D:

All 19 focus points are “cross” focus points, and the center is “double cross” focus points. This is a strong guarantee for 7D’s powerful focusing ability.

Canon 50D in the mid-range:

It is a 9-point full “cross” with a central “double cross” focus sensor.

Low-end Canon 500D:

Although the focus is also at 9 points, only the central point is a “cross”, and the other 8 points are just “one-word” focus sensors.

In this way, when dealing with low light, large aperture and dynamics, where the focusing ability is demanding, the Canon 500D is far behind the 50D, and it lags behind in focusing speed and accuracy.

Because of the difference in focusing ability, if a low-end camera chooses a large-aperture lens, sometimes the optical quality of a large-aperture lens cannot be used (low-end cameras have poor focus and can’t take advantage of the advantages that a large aperture can bring). For example, if you use 500D with Canon 50/1.2L, you may not be able to get a clear image when using an aperture smaller than F2.8, because the camera’s focus accuracy is not enough. This is determined by the positioning of the camera.

Some expensive professional quasi-zoom lenses mostly have an aperture of F2.8 or even larger. A larger aperture can ensure more light input, and can still obtain a sufficiently high shutter speed under low light conditions to obtain a clear image. But while the large aperture brings more light in, it also makes the depth of field of the photo subject become very shallow. If you are shooting documentary photography, the content of the background of the screen cannot be ignored.

Photosensitive element

High resolution and high definition are two concepts. Pixels only determine the size of your photo. A very blurry photo may also have high pixels.

In the film age, according to the size of the film, we can divide cameras into: APS format, 135 format, 120 format, and large format.

→135 format camera:

Use the most common 35mm film, the film size is 24*36mm. The full frame of today’s digital SLR era is 135 frames.

→APS frame:

Less than 135 frame system.

Full frame and APS frame only differ in the size of the photosensitive element. Most of the full-frame digital SLR lenses from the same manufacturer can be used on APS-frame digital SLR cameras.

The photosensitive element cannot record all the thresholds of natural light from the brightest to the darkest (just as the number of colors that a computer screen can display cannot record all the colors of the natural world), for example, suppose the light level of the natural world can be divided into 10 levels (1 The darkest, 10 is the brightest), then the photosensitive element can only record up to 6 levels. Therefore, when shooting, we have to consider where to put these 6 areas in the 1-10 level area. For example, suppose we want to record more levels of the bright parts, we put all the 6 levels of the photoreceptor on levels 4-10 of the 10 levels in nature, and abandon the 4 levels describing the levels of the dark parts.

Similarly, suppose we want to record more of the dark parts of the scene, then we will assign 6 levels to the 1-6 levels in the natural world, and give up the 7-10 light levels.

If you want to show the details of the dark part, use the dark part as the metering basis. If you want to express the details of the highlights, use the highlights as the basis for metering. In practice, in most cases, more levels of highlights are preserved.

Scenery photography, usually morning and evening photography, 6-9 in the morning, 4-7 in the afternoon, in the middle of the time is a rest.

Why do ordinary photography often emphasize the choice of morning and evening as the shooting time? The reason is that the position of the sun in the sky in the morning and evening is lower, and the projection of objects is often longer. This kind of light and shadow effect can make the level of the picture richer and more durable.

Moreover, in the morning and evening, the difference in brightness between the sky and the ground is smaller than at other times, and the latitude of the photosensitive element can be fully utilized to bring rich layers to the picture. (Rather than the sharp contrast between bright and dark under strong light, the camera exposure can not take into account both the bright and dark parts. Either the bright part details or the dark part details are lost.) In other words, in order to make the picture richer, we must make the main body of the picture and The background is controlled within the range that the photosensitive element can express.

Sensitivity ISO

Photos are blurred, often because the shutter speed is too slow. We can adjust the size of the aperture, that is, the larger the aperture, the more light enters, and the shutter speed can be increased. But sometimes even at the maximum aperture, sufficient exposure cannot be guaranteed, and the shutter speed cannot be increased, resulting in blurry photos. Then, we need to use “sensitivity ISO” to increase the shutter speed.

“Sensitivity” is a quantitative value of the ability of photosensitive materials to perceive light, and the international unit is ISO. Common sensitivity classifications are: ISO100, 200, 400, 800, 1600, 3200, 6400, 12800. Every increase of 1 level (for example, from 100 to 200), the light sensitivity is increased by 1 time, which is equivalent to the light intensity increased by 1 time, so that we can also increase the shutter value by 1 level accordingly.

Low sensitivity	Medium sensitivity	High sensitivity	Ultra high sensitivity
Below ISO100	ISO 100~200	ISO 400~800	Above ISO1600

Therefore, when the aperture is the same and the shooting scene is the same, the exposure time (shutter speed) is inversely proportional to the sensitivity.

So, now we know that the three major elements of digital SLR control exposure are: aperture, shutter, and sensitivity.

Some cameras can subdivide every two levels of sensitivity into 1/3 levels of adjustment. For example, between 100 and 200, divided into 3 levels, there are more fine sensitivity values ​​such as 100, 125, 160, and 200. The purpose of this design is actually to use “low sensitivity” as much as possible under a stable shutter. Because the higher the sensitivity, the side effect is that it will increase the noise of the picture, and the sharpness of the picture details, color saturation, color deviation, picture level and picture contrast will be severely affected.

For ASP frames, below ISO400, the noise problem is not obvious. But if you can use low sensitivity, don’t use high sensitivity. For full-frame digital SLRs, the high-sensitivity effect is much better than that of APS frames, so the scope of application can be increased by 1-2 levels.

Of course, for handheld shooting in low light conditions, you should first ensure the clarity of the picture (the value of high sensitivity is here), and secondly consider the loss of image quality caused by high sensitivity. Because the picture quality is not perfect, it can still be used, but if the picture is blurred, it will be “useless”.

Shooting flowing water for a silky effect is to extend the exposure time, but the lowest sensitivity (ISO50 or 100) should be used (because the exposure time itself is already very long.)

Lens

The structure of a digital SLR lens is more complicated. No lens has the function of a single lens. A lens is usually composed of multiple lenses. The lenses are grouped according to design needs. Therefore, manufacturers usually use “several groups of several lenses”. Way to describe the internal structure of the lens.

Product positioning of the lens:

In order to cater to different consumers, manufacturers usually provide multiple lenses for selection at the same or similar focal lengths, which correspond to beginners, enthusiasts, and professional photographers. Therefore, according to different levels, the functions of the lens are differentiated. Professional lenses for high-end users often have larger apertures and volumes to load more lenses, obtain larger apertures and better image quality. At the same time, new technologies such as anti-shake and ultrasonic motor focusing are also preferentially installed on these lenses.

Aperture F

The larger the aperture, the smaller the depth of field. The smaller the aperture, the greater the depth of field

Common aperture values ​​are:

1—1.4—2—2.8—4—5.6—8—11—16—22—32

The difference between each level of aperture is 1 times the brightness. The smaller the number, the greater the brightness.

F1 aperture (F1 is the largest aperture) means that the brightness seen by the human eye through the lens is the same as the brightness of the scene seen by the naked eye in daily life, and this is used as the benchmark for the aperture.

Beginners should know that although it is a lens, the image quality of different apertures is different. According to the optical characteristics of the lens, when the maximum and minimum aperture of the lens are used, the imaging quality of the photo will be reduced to varying degrees.

Generally speaking, the imaging quality of the maximum aperture of the lens is often not ideal, and a smaller aperture will improve the imaging quality a lot. The best aperture of the lens is generally the maximum aperture contraction of 2 levels. Therefore, the larger the aperture of the lens, the more the number of apertures that can be selected for high imaging quality, and the more expensive it is.

The best imaging quality aperture of the lens is F8 or F11, and the aperture is larger or smaller than them, and the imaging quality gradually decreases.

In landscape photography, in many cases, a smaller aperture is used to obtain a greater depth of field and richer details. Therefore, at this time, the difference between the ordinary lens and the “bull head” is very small.

Shutter

Safety shutter=1/focal length of lens

Between each level of the shutter speed, it also basically increases by 1 times:

8 seconds, 4 seconds, 2 seconds, 1 second, 1/2 second,…1/8000 second

We can get the same exposure value (Exposure value, abbreviated EV) through many different combinations of aperture and shutter. For example, the shutter combination of aperture 5.6 & 1/250 second, and the combination of aperture 4 & shutter 1/500 second, will get the same exposure.

In other words: exposure value = aperture + shutter.

Safe shutter speed:

When the shutter speed is too slow, your hands will easily shake off, resulting in blurry pictures. In the era of film photography, there is a “safe shutter” concept: that is, when the shutter speed is the reciprocal of the focal length, it can ensure the stability of the camera when holding it. That is the formula: safety shutter = 1/focal length of the lens.

For example, if you use a lens with a focal length of 50mm, the shutter speed cannot be lower than 1/50 second. This is a reference quantity. In the digital age, this reference is often still higher. Because in the film age, few people would zoom in to see the clarity. Now, even if you only use the 100% zoom ratio to view the photos on the computer, you will find that even under the safe shutter, the sharpness of the photos is still not guaranteed. Therefore, the shutter speed needs to be increased.

Depth of Field

The longer the focal length, the smaller the depth of field; the shorter the focal length, the greater the depth of field.

As mentioned above, the shutter combination with aperture of 5.6 & 1/250 second, and the combination of aperture 4 & shutter 1/500 second, get the same exposure. But although they get the same amount of exposure, the imaging effect of their photos is different-the clear range of the front and back of the main body of the picture is different, which leads to the concept of “depth of field”.

The larger the aperture, the smaller the depth of field (the background can be blurred, such as when shooting people). The smaller the aperture, the greater the depth of field (far and near are equally clear, such as when shooting landscapes).

4 factors that affect the depth of field:

①The size of the aperture:

The larger the aperture, the smaller the depth of field (the background can be blurred); the smaller the aperture, the greater the depth of field (the same clear before and after).

②The focal length of the lens:

The longer the focal length of the lens, the smaller the depth of field. The shorter the focal length of the lens, the greater the depth of field. For the same zoom lens, the depth of field at the wide-angle end is much larger than that at the telephoto end. Some zoom lenses, even if the aperture is reduced by 1-2 stops at the telephoto end, the depth of field obtained by opening the aperture at the wide-angle end is shallower.

The telephoto lens has a strong ability to blur the background, and the large aperture also has a strong ability to blur the background. But what cannot be ignored is that when using a telephoto lens, the distance between the lens and the subject is usually relatively far. In this case, if you don’t pay attention to the distance between the subject and the background, you may not get a good blur effect. Therefore, finding the right angle to extend the distance between the subject and the background is still the first consideration.

③The distance between the subject and the lens:

When taking pictures, the closer the lens is to the subject, the smaller the depth of field. The further away the lens is from the subject, the greater the depth of field.

④The distance between the subject and the background:

The further away the subject is from the background, the more blurred the background. The closer the subject is to the background, the clearer the background.

Therefore, if you want to blur the background, you can use the above four methods.

Metering Method

The current digital SLR has at least three metering methods, such as evaluative metering, spot metering, center-weighted average metering, and partial metering.

No matter which kind of light metering method, the principle is the same, that is, “18 degrees gray”. “18-degree gray” is a gray that reflects 18% of light. This kind of gray card paper is also sold in equipment stores, also known as “18-degree gray card.” This reflectivity is roughly equivalent to the reflectivity of the back of the yellow hand. When the camera finds that the brightness of the scene in the viewfinder is brighter than “18 degrees gray”, it will think that the light is relatively strong, and the metering indicator will reduce the aperture or increase the shutter speed. Conversely, if the camera finds that the brightness of the scene is darker than “18 degrees gray”, it will expand the aperture or reduce the shutter speed.

However, depending on the machine to measure light, the error in actual work is very large. This is related to the following factors: ① the position and size ratio of the subject in the screen, ② the brightness difference between the subject and the environment, and ③ the color and brightness of the subject.

Due to the size ratio:

For example, when we shoot a person backlit in the sun, the smaller the proportion of the person in the picture, the larger the proportion of the high-brightness background. In this way, the camera will think that the whole picture is very bright and give a smaller proportion. The metering data of aperture or increased shutter speed will mislead you, resulting in underexposure of the subject in the photo.

Due to the color of the subject itself:

For example, coal is black and snow is white. When the camera is pointed at the black coal, it cannot distinguish whether the black is caused by light or the object itself is black. Then even in the daytime, the camera will think that this black is much lower than the brightness of “18 degrees gray”, thereby increasing the exposure, then the coal will eventually be photographed as gray. Similarly, for white snow, the camera will mistakenly believe that the light is very strong, will reduce the exposure, and shoot the snow in gray.

In normal photography, we often encounter shooting the moon, but the moon can easily be overexposed. The moon itself is very bright. If you want to make the moon photographed clearly, then the objects on the ground will often be seriously underexposed. It can be seen that it is almost impossible to express the level of the moon and the level of ground objects together. You may have seen perfect photos of the moon and ground objects, but most of them were done later.

In order to solve the above problems, there are several light metering methods:

 

“Zone metering”

That is, multiple areas are divided within the metering range, and then each area is metered separately, and the weight of each area is calculated according to the location of the subject person to obtain a metering value that takes into account the subject and the environment. To reduce the degree of metering error.

“Spot Metering”

It is to directly meter the subject without considering the ambient light.

When the main elements that need to be expressed in the picture are all concentrated, in order to make the subject exposure correct, the “spot metering” mode should be selected.

“Partial Metering”

It can be seen as the expansion of the metering area of ​​”spot metering”.

Center-weighted metering

This mode is very suitable for taking group photos.

These metering methods can greatly reduce the exposure error, but still can not completely solve this problem. Obviously, the camera can only give a reference metering value, you can’t completely believe it. We also need some means of artificially predicting light-this is “manual exposure” and “exposure compensation”.

Spot metering, center-weighted average metering, partial metering, etc., for each metering method, there are errors. Among them, the “center-weighted average metering” has the largest error. So since the error is so large, why should it remain in modern cameras? Because an old photographer, if he keeps shooting with this metering method, he will know very well what kind of “exposure compensation” needs to be done under what environment and how much compensation. And if you switch to “zone metering”, then this compensation value needs to be changed. In other words, his previous experience may not be used.

Some friends often change the light metering method. For a while, they feel that the subject needs “spot metering”, then they feel that the environment needs “zone metering”, and then they feel that the subject needs “local metering”. It is impossible to develop a good experience for a certain type of light metering in a short period of time by changing the metering method frequently. In other words, as a novice, using a fixed metering method can get more metering experience in a short period of time. Based on this point, we recommend using “zone metering” as a common metering method.

Use of Catch Light

The light source used as the catch light does not require strong power, but it must be coordinated with the environment. Anderson believes that, personally, he would rather choose natural light as the source of eye light. Indoors, it is best to try the light coming in from a window beyond your shoulders to create a catch light, even if it is not the main light source. It is much more natural to use a reflector outdoors than to use an auxiliary flash, especially for close-up photos. Also try to avoid the reflection of the white of the eyes to the main light source, it can only glow with white light tastelessly, making people’s eyes out of balance.

Soft-tone Portrait Lighting

Soft-tone portrait lighting is a uniform city lighting method with a total tone of intermediate colors. This kind of lighting basically uses multiple lamps and several reflectors. Direct, diffuse and reflect the light to the subject. If the lighting is cleverly arranged, you can shoot quite wonderful portraits.

In order to obtain a uniform, comprehensive, soft tone and beautify the lighting effect of the subject, generally 3 indoor photography lights and some reflectors are used. Use two large 300-watt plus soft spotlights side by side in front of the subject. The two lights should be at a certain angle with the subject and a aluminum-coated reflector mounted on a bracket in front of him. In this way, the uniform lighting effect can be achieved by the distribution of light, which is to maximize the intensity of the reflected light. Therefore, the reflector is a critical part of lighting. The headlight should be set quite high and placed on the left side of the subject, just behind his head. Some reflectors can be placed behind and on both sides of the subject to increase reflection.

For specific shooting, first turn on the two soft spotlights in front of the subject, and adjust the angle so that they can evenly illuminate the subject, and at the same time make the aluminum-coated reflector in front of the subject reflect upward Maximum amount of light. A reflector was set up behind the subject, and a white, long cylindrical reflector was also set up in the left example. Then, set up the headlight and raise it to produce strong and uniform illumination on the subject’s left shoulder. The headlight should be high enough to hit the light directly on the reflector mounted on the bracket in front of the subject. Move your hands back and forth on each reflective surface to check the reflective effect, and finally determine the exposure level and start shooting.

Rembrandt-style Light

Rembrandt is a world-renowned Dutch painter. Rembrandt-style lighting is a special lighting technique specially used for shooting portraits. When shooting, the shadow side of the subject’s face is facing the camera, and the light illuminates three quarters of the face. The portraits taken with this light method resemble Rembrandt’s portrait paintings, hence the name.

The Rembrandt-style lighting technology relies on strong side lighting to make any side of the subject’s face present a triangular shadow. It can divide the subject’s face into two, while making the sides of the face look different. If uniform overall lighting is used, both sides of the subject’s face will look the same.

This lighting technique is quite effective because it highlights the subtleties of each face, that is, the sides of the face are different. The lighting effect can also be adjusted arbitrarily with auxiliary light according to the wishes of the photographer: Although the high-contrast form of Rembrandt-style lighting is interesting, the appropriate use of reflectors and auxiliary lights can minimize the contrast and enhance the whole The effect of portrait, so as to shoot extraordinary works.

Generally, the use of Rembrandt-style lighting requires two lamps to illuminate, and after improvement, a third lamp is added to adjust the contrast. Among the two illuminators, a 650-watt quartz main light (A) is placed on the upper left of the photographer, directly illuminating the right side of the subject’s face, just like a soft light auxiliary light (B) on his front , But the latter is placed on the photographer’s left. The white long strip reflector is placed on the left side of the subject.

It can reflect some light to the unlit case of the face. The headlight (C) can shine light on the face of the subject through the reflector, weakening the obvious Rembrandt triangle and brightening the overall tone of the portrait.

For specific shooting, first turn on the 650-watt quartz main lamp (A) and adjust its angle so that the Rembrandt triangle light is cast on the dark side of the subject’s face. Then turn on the main soft light (B) on the front, directly facing the bright side of the subject’s face. It can illuminate the subject’s face and increase the depth, but at this time the triangular bright area is still obvious. Try to make the subject turn his head until the Rembrandt triangle light shines on his cheek just right. And ask the subject’s chin to tilt down. The next step is to meter the light and select the camera’s aperture and shutter combination. Finally, check the background again to see if the hair light will leave bright spots on the background and cause flare in the camera lens. When you start shooting, you can talk easily with the subject so that he can relax and smile. This step is also very important. It must be remembered that the important thing in portrait photography is not to let the effect of a technique exceed the expressiveness of the subject’s face.

Side Portrait Lighting

Shooting a profile portrait has a strong appeal to the subject, because people generally don’t have the opportunity to look at their image from this angle. American photographer M. Richard believes that in order to take a good example of a portrait, in addition to a good pose of the subject, a special lighting method must be used to give the photo a special sense of beauty and a powerful charm. And a deep sense of space.

Richard’s experience is that, first of all, the side shoulder of the subject should be at a 45-degree angle to the optical axis of the lens, not parallel to the optical axis of the lens. And make him sit higher so that his nose is perpendicular to the optical axis of the lens. When taking portraits of men, Richard likes to keep their chins slightly lower and their heads slightly towards the background. But no matter which direction the head of the woman’s profile faces-up or down, left or right, the effect works well. The direction of the eyes is also important. The pupils of the eyes of the subject are best to be perpendicular to the optical axis of the lens. Look up when the head is slightly tilted, and look down when the head is lowered.

Regarding the side portrait with light, Richard’s general idea is to arrange strong light from the eyebrows to the cheeks, and try to avoid “hot” the subject’s forehead, eyes, and hands. When taking a side view, three lights and a reflector are generally used to illuminate the face of the subject.

High-contrast Portrait with Light

Taking a high-contrast portrait with no normal pitch is an interesting attempt in black and white portrait photography. It can create some vivid and moving images by using contrasting bright, hard light.

In order to obtain such a high-contrast portrait, in addition to the considerable skill in exposure and development, there are also certain requirements for the lighting when shooting. American photographers J. Mitchell and J. Hannum proposed a simple lighting method in an article in “Darkroom Photography” magazine:

Direct light or scattered light can be used for illumination, generally one lamp or two lamps are better. For the convenience of shooting, it is best to use a spotlight so that you can directly observe the light effect. Of course, flash can also be used. In most cases, only one lamp is sufficient.

If the subject’s hair is very dark, then a second light can be used to directly illuminate the subject’s hair or illuminate from behind to produce a brighter outline that distinguishes the subject from the background.

In order to achieve a moving effect, you can try to illuminate the subject with side light or 45-degree angle of light. Side light only illuminates half of the face of the subject, while 45-degree light can illuminate most of the face, and creates a triangular bright part on the cheek facing the light source.

This high-contrast effect looks best with a dark, unlit background. In order to better distinguish the image from the background, you can brighten the subject’s head with light: Backlit silhouette portraits are actually also It can be regarded as a high-contrast portrait photography.

British photographer M. Kipling pointed out that a backlit photo is the contour image effect of the subject with the light source behind it. Generally, the tolerance of photographic film to feel and express tones is very limited. In contrast, the human eye has a much wider range of perception of tones. In this way, in the photo, darker objects can jump out in silhouette against the brighter background.

For backlit silhouette photos, daylight is often used as the light source, but any light can be used as the light source according to the photographer’s convenience or preference. Kipling believes that it is ideal to take backlit silhouette photos with the sky after sunset or before sunrise as the background. In order to produce a good backlight silhouette effect on the negative, the ratio of the brightest part to the darkest part of the photo is usually 50:1. This is especially true when shooting with a slideshow, because the tone latitude is narrower.