How to grasp the exposure time when taking pictures in rainy days

1. The characteristics of light in rainy days are mainly scattered light, and the sky light is very soft. However, the brightness of scattered light is much higher than that of clear blue sky. Only when dark clouds are rolling and heavy rain is coming, the brightness of the sky is lower than that of clear Wan Li. Compared with the clear sky, the skylight at this time has the following situations: (1) Before the rainstorm, dark clouds rolled and the sky was dark, and the light amount was only115-in the clear sky. (2) Generally, on cloudy days before rain, the light quantity is sunny1/3-1/5; (3) The light quantity on cloudy days is 1/4- 1/8 on sunny days, (4) The light quantity on cloudy days is1/7-110 on rainy days; (5) In a gray sky without the sun, the light quantity is sunny 1/2- 1/5. According to the above different situations, under the condition of constant shutter speed, the aperture is higher by 1-6 levels than that in sunny days. 2. The light in rainy days will also be affected by the shooting environment. In forests, narrow streets or lanes, the light in rainy days is darker than in open areas. The light near the water is brighter than that where there is no water. The scattered light in rainy days has little difference between the horizontal plane and the vertical plane of the object, which is basically equal, unlike the obvious contrast between light and shade in sunny days. The surface brightness of objects in rainy days has nothing to do with the displacement of the sun. 3. If you take color photos in rainy days, you should also pay attention to the problem of color temperature, because color film is very sensitive to the change of color temperature. Atmospheric media in rainy days, such as water vapor, smoke, dust, etc. , can scatter all wavelengths of visible light and make it white, so it will not be affected by atmospheric media like direct sunlight and change the color temperature. Generally speaking, the color temperature is high in rainy days. It is relatively stable and monochromatic, so taking color photos in rainy days can't consider the change of color temperature according to the height of the sun in the sky like in sunny days. 4. Although it is scattered light in rainy days, there is no obvious contrast between light and shade, but there is still a weak contrast between light and shade according to the direction of the sun or the thickness of clouds in the sky. In order to achieve better shooting results, the following specific measures should be taken: (1) Use low-sensitivity film. (2) use a large aperture to highlight the foreground and blur the background; (3) reduce the exposure during development and prolong the film development time; (4) When shooting, make full use of the background and contrast to highlight the subject; (5) When shooting a close-up human body, avoid taking the sky as the background, which can prevent people's faces from being underexposed. 5. When shooting with color negative film in rainy days, there is generally no need to use filter, and the color can be corrected when printing.