Photographic lighting problem

1. Controlling the area and diffusion degree of the light source is directly related to the luminous characteristics of the light source, and then affects the contrast between light and dark of the subject. Therefore, controlling the area and diffusion degree of the light source can better control the contrast effect of the subject. When low contrast is needed, the light source area is large and the diffusion degree is large, so that the light coverage exceeds the subject; When Gao Fancha is needed, the light source area should be small, the diffusion degree should be small, and the light should be directional. 2. Ensure sufficient lighting brightness. Sufficient illumination brightness enables us to freely control the required depth of field through the aperture. Although it can be solved by extending the exposure time or making multiple exposures in the case of insufficient illumination brightness, both methods will bring inconvenience to shooting. Prolonging the exposure time will easily lead to the invalidation of the law of exposure reciprocity, which will lead to the coarsening of picture particles, the decrease of contrast and the color deviation. However, the use of multiple exposures requires that the positions of the subject and the camera do not move during the exposure process, and the calculation of exposure is more complicated, which greatly increases the difficulty of shooting. 3. Choose the appropriate lamp distance First of all, the lamp distance directly affects the light intensity of the subject. The light intensity of the object changes according to the reciprocal of the square of the lamp distance, and the light intensity changes greatly with the lamp distance. In addition, the light distance will also affect the contrast effect of the subject. When the lamp distance is small and the light source area is smaller than the subject, the light source can be regarded as a point light source, and the contrast of the subject is large; On the contrary, when the lamp distance is large, the light source can be regarded as a surface light source, and the contrast of the subject is small. 4. Use lamps as little as possible. It is not that the more lamps are used, the better. Using too many lamps not only makes the light distribution complicated, but also brings chaotic projection, which is often difficult to eliminate. Therefore, in light distribution, lamps should be used as little as possible, and reflectors can be selected to fill the light when necessary. 5. Multi-purpose reflector advocates the use of reflector in lighting, which is not likely to produce disgusting projection, but also because various reflectors can provide reflected light with different light properties, which is convenient for controlling the effect. The reflector can be used as both the main light illumination and the auxiliary light illumination of the dark part of the subject. It can even be cut according to the needs of light distribution and the shape of the subject, which can supplement some parts of the subject and control the light field well. In advertising photography, the number of reflectors often exceeds the number of lamps. For an advertising photographer, whether he can use the reflector flexibly and effectively is a sign of whether his lighting is mature or not. 6. Proper light ratio control The light ratio control in lighting involves the contrast of the subject itself and the contrast between the subject, companion and background in the picture, and also determines the tone of the whole picture and the texture and details of the subject. The control of light ratio in cloth light is generally based on the principle of truly expressing the inherent surface brightness, texture and color of the subject itself. For example, the white subject should be elegant and clean, the subject should be high-key, and the black subject should be deep and dignified. Of course, under the premise of not violating advertising creativity, photographers can also creatively control the light ratio according to their own personality and habits in order to obtain new ideas in lighting.