Is the aperture in photography represented by F? Is there a difference between F and F?

There is no difference. F sometimes stands for aperture, sometimes for focal length, and so does F.

For the manufactured lens, we can't change the diameter of the lens at will, but we can control the luminous flux of the lens by adding a polygon or circular aperture grating with variable area inside the lens. This device is called an aperture.

Aperture f value = lens focal length/lens effective aperture diameter. As can be seen from the above formula, to achieve the same aperture f value, the aperture of a long focal length lens is larger than that of a short focal length lens.

Extended data:

The function of the aperture is to determine the amount of light entering the lens. When the shutter is constant:

The smaller the values behind 1 and f, the larger the aperture, the more light entering, the brighter the picture, the narrower the focal plane and the more blurred the background of the subject.

2. The larger the value behind f, the smaller the aperture, the less light entering, the darker the picture, the wider the focal plane, and the clearer the front and back of the subject.

Note: The simplest camera only has a fixed aperture Waterhauser aperture with a round hole.

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