What are the sixteen rules of sunshine?

The basic law of sunshine 16 is as follows: when it is sunny outdoors, if the aperture is f/ 16, the shutter speed should be the reciprocal of the international sensitivity index of the film used. For example, in outdoor sunlight, the aperture is f/ 16 and the film sensitivity is EI 100, then the shutter should be1100 second.

"16" in the formula does not mean that the aperture must be f/ 16. If f/ 1 1 is selected, the shutter speed will be doubled to 1/200 seconds, and so on. Secondly, it should be adjusted according to the weather conditions. If it is cloudy instead of sunny, use EI 100 film. If the shutter speed is still1100 seconds, then the aperture should be doubled from116 to1100. And so on.

The function of aperture:

1, which can adjust the amount of light entering the lens. For example, domestic kittens always shrink their pupils into a line during the day, and automatically Zhang Kaicheng a round hole at night.

2. Aperture is the most important factor to determine the depth of field, including small aperture (large aperture value), depth of field, large aperture (small aperture value) and depth of field. For example, nearsighted friends, if they don't wear glasses, always habitually squint at things, so they can often see things clearly. Applying photographic terminology, this is called: narrowing the aperture (pupil) and increasing the depth of field.