The method of adjusting the aperture of the 5D3 is as follows:
Turn the mode dial to Av, turn the dial to set the desired aperture value, turn the mode dial to M, turn the dial to set the shutter speed, and turn the dial to set the aperture. See pages 164-166 of the electronic manual for more detailed instructions. In P, to change the program exposure combination, press the shutter button halfway and turn the dial to change the shutter speed and aperture combination.
The aperture is a device used to control the amount of light that passes through the lens and enters the light-sensitive surface inside the camera body, which is usually inside the lens. To express the size of the aperture we use the f-number.
It is not possible to change the diameter of a lens that has already been manufactured, but we can control the amount of light that passes through the lens by adding a polygonal or circular, variable-area aperture grating inside the lens, which is called an aperture.
As we already know, the speed of a lens is its ability to transmit light. If we don't want the lens to admit the maximum amount of light, we need a way to reduce the amount of light from the lens. We do this by utilizing a method of changing the size of the lens aperture. The aperture is the circular hole in the center of the lens created by the variable aperture (blade group).
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