Table of Contents
Techniques of Borrowing Light in Photography
The closer the light source, the softer the light. Conversely, the farther the light source is, the harder the light. This is because when the light source is closer to the subject, the relative larger, that is, the wider. And when the light source is farther away from the subject, the relative smaller, that is, narrower.
- The wider the light source, the softer the light
Conversely, the narrower the light source, the harder the light. A wide light source can weaken shadows, reduce contrast, and suppress texture, while a narrower light source has the opposite effect. This is because the wider the light source, the more the direction of the light on the object, which will increase the lighting in the scene and reduce the shadows.
Tips: When the main body of the portrait is arranged by a large and bright window that is not exposed to direct sunlight, the window can act as a soft box and no special equipment for the studio is needed.
- The closer the light source, the softer the light
Conversely, the farther the light source is, the harder the light. This is because when the light source is closer to the subject, the relative larger, that is, the wider. And when the light source is farther away from the subject, the relative smaller, that is, narrower.
Take the sun as an example. The diameter of the sun is 109 times that of the earth. It is a very wide light source! But the sun is 93 million miles (about 150 million kilometers) away from the earth, which is only a very small part of the earth’s sky, so the light is hard when the sun shines directly on the object.
Tips: When shooting portraits with existing lights indoors, you can change the distance between the light source and the subject to make the light more moving. 
- Diffuse scattering can disperse light, widen the light source and soften the light
The essence of using diffuse scattering to disperse light is to widen the light source, so as to achieve the purpose of softening the light. When the clouds block the sunlight, the shadows on the object will be significantly reduced. If there is fog, the shadow will disappear. Clouds, gloomy sky, and heavy fog will diffuse light, and diffusion will spread light in all directions. On cloudy and foggy days, the entire sky will become a very wide light source, a natural soft box.
Tips: Materials such as translucent plastic or white fabric can be used to diffuse strong light. You can add a diffuser in front of an artificial light source, such as a studio flash; if it is in bright sunlight, you can also use a soft light awning or soft box to soften the light.
- Diffuse light in reflection
Shoot a narrow beam of light on a larger frosted surface, such as a wall, roof or frosted reflector, and the light will be diffused to a wider area during the reflection process.
But if you use a glossy reflector, the light will still be narrow after being reflected. A mirror is an extreme glossy reflector, the light it reflects is almost as narrow as the incident light.
Tips: Knead a large piece of aluminum foil into a ball, unfold the bright side outwards, and wrap it on a piece of cardboard, and a soft light reflector is ready. Although the diffusion effect of this homemade reflector is not as good as the white frosted reflector, it can add sparkling light spots in the photo.
5. The farther the light source, the faster the attenuation of the light and the darker the subject
This rule states that the illuminance of the subject is inversely proportional to the square of the distance. This sounds complicated, but it’s actually very simple. For example: if you double the distance from the light source to the subject, then the light falling on the subject will only be a quarter of the distance before the increase.
In other words, the light will rapidly attenuate as the light source moves away. We should keep this rule in mind. If you are going to move the light source or subject, you must change the quality of the light.
Also note that the distance traveled by the reflected light will increase, even if a glossy reflector is used.
Tips: Flash should be used when shooting portraits outdoors in bad weather conditions (hot shoe or pop-up type is acceptable). In this way, the shadow on the human face can be eliminated, and the exposure of the background will not be affected, because the light from the flash reaches the background and is already weak enough to be negligible.
- Light attenuation can be used to change the relationship between the photographic subject and the background
If the light is close to the subject, the difference in illuminance between the subject and the background will be more obvious. If the light is far from the subject, the background will brighten accordingly.
The same principle applies to side light: when the side light source is close to the subject, the light attenuation of the whole picture will be more obvious than when the light source is far away from the subject.
Tips: If the front light of the subject is the light coming in from the window, then bringing the subject close to the window can darken the indoor background. If you want to make the indoor background brighter, you should keep the subject away from the window and close to the background. 
- The front light will weaken the texture of the subject, while the side light, top light and bottom light can strengthen the texture of the subject
Portrait photographers usually keep the light source near the axis of the lens to reduce wrinkles on the subject’s face. Landscape photographers prefer to use side light to emphasize the texture of rocks, sand and leaves. Generally speaking, the greater the light direction and the angle of the subject, the more obvious the texture of the subject.
Tip: When you want to highlight the fluffy hair of your pet, it is best to place the light source on the side instead of using a front light source.
- Shadows create three-dimensionality
Shadows are a way for photographers to describe the three-dimensionality of objects. It can make the object present a sense of space in the photo, not just the projection of the object on the plane.
Similarly, the side light, top light and bottom light can cast deep and long shadows on the object to create a three-dimensional effect. Therefore, still life, commercial products, and landscape photographers like to use angled light.
Tip: You can try to use the “Hollywood Lighting Method” to shoot dramatic portraits. Place the top light at a position slightly above the subject and adjust the light angle so that the shadow of the character’s nose falls on the position slightly above the lips.
- The backlight can be used as a highly diffuse light source
There are very few objects that are only illuminated by backlighting, that is to say, there are almost no pure silhouettes without any frontal illumination. If a person stands in front of a bright window, the opposite wall will reflect part of the light falling on the person. If a person is outdoors, even if the background is bright sunlight, there will be light from the sky on the front. In either case, if you want to record the light falling on the subject, you must increase the exposure, and these lights will reduce the details of the face and weaken the three-dimensional sense of the subject.
Tips: When shooting backlit portraits or silhouettes, try to incorporate the light source into the composition, but this will cause inaccurate light meter readings, so you can try to use bracketing.
- Light is colorful
Although sometimes the light looks like “colorless”, it is actually colored, and we call it color temperature. It’s just that the “computer” composed of our eyes and brain can adjust perception and adapt to changes, so it’s hard for us to notice it. But digital sensors and film will record colors that we can’t see.
The sun in the morning and evening has warm tones, and the shadows cast by the sun at noon turn blue. The tungsten filament light is obviously yellowish, and the surface reflecting this light will also show the corresponding color.
For digital cameras, you can use the white balance function to eliminate or emphasize the color of light. For example, you can add warm colors in landscape or portrait photos. For film movie shooting, you must select the appropriate film according to the shooting environment, or use filter compensation.
Tips: Scenery shots on sunny days, especially the shadows, will be very blue. At this time, setting the white balance of the camera to cloudy can add golden yellow to the photo, which is equivalent to adding a warm color filter in front of the lens.
The Use of Lighting in Photography
Light is the most important constituent element of photography, and the treatment of light is often more important and difficult than other elements. Light not only makes the target image on the camera’s CCD, but a good photographer can also express different moods by using light of different nature.
Intensity of Light
Intensity describes the intensity of light, and the light emitted by various light sources has a certain intensity.
the cabin can retain details under soft light
Strong light is usually caused by direct light from a strong light source. Of course, the weaker light source can also form a strong beam by concentrating. Strong and direct light will cause obvious shadows and clearly show the outline of the object, so it is often used to outline the outline of the object. Strong light can also increase the contrast between light and dark of the subject to emphasize the texture of the surface of the object, the contrast between different colors or tones. Weak and scattered light can reduce the contrast of light and dark of the subject, making the surface of the object look smooth and detailed.
For photography lighting, strong light sources are often used as the main light, which is the main source of photography lighting. The weak light source should be used as an auxiliary light, it can weaken the strong shadow caused by the main light, and at the same time will not cast unnecessary shadows.
However, if the light is too strong, very good results are often not received, because the shadows formed under strong light will be too exaggerated and the light and shadow effects are unnatural. When shooting, if the light is too strong, you can reduce the intensity of the light by installing a diffuser or reflector.
Compared with strong light, the light and shadow effect of astigmatism is softer and more natural. The light-receiving surface of the main body can be uniform, the contrast is moderate, and the directivity of the light source is limited, making it an ideal light source. In the shooting of feature films, astigmatism is used the most.
Illumination
The illuminance, which is commonly referred to as lux, represents the luminous flux per unit area on the surface of the subject. 1 lux is equivalent to 1 lumens per square meter, that is, the luminous flux that is vertically irradiated by a light source with a distance of one meter and a luminous intensity of 1 candela per square meter of the subject. Illumination is an important indicator to measure the shooting environment.
When the sun is strongest at noon in summer, the outdoor illuminance can reach more than 100,000 lux, and it is easy to form obvious shadows. This is not necessarily an ideal shooting environment. Most indoor illuminance is below 300 lux, and ordinary cameras can shoot under this illuminance.
However, the lower the illuminance, the more likely it is to take a gray or grainy image, so it is better to increase the lighting. The ideal shooting condition is that the illumination is about 10000 1ux. Shooting in such an environment, it is easy to get clear and bright images.
The illuminance is not only related to the luminous intensity of the light source, but also related to the distance from the light source to the subject. In general, when the distance from the subject to the light source does not change, the illuminance of the subject is proportional to the luminous intensity of the light source.
On the contrary, when the luminous intensity of the light source does not change, but the distance from the subject changes, the illuminance on the subject is roughly inversely proportional to the square of the distance.
When a light source illuminates the front and back two subjects, the closer the light source is, the greater the difference in illuminance between the two subjects. The farther the light source is, the closer the illuminance the two subjects receive.