Solutions to the problems of camera flange distance and focal length

A lens is a lens system composed of many lenses, including not only convex lenses but also concave lenses. The interaction of multiple lenses finally forms a clear image on the negative. Even a fixed-focus lens with the least number of lenses needs at least two lenses (theoretically).

But you're also right. A lens with the best quality and a negative with the best quality will surely take the best photos (don't get stuck in a dead end).

The focal length is the distance from the point in the lens of the lens to the point where the light can be clearly focused. The focal length of the lens logo is its maximum focal length. A zoom lens with a maximum focal length of 200mm may not only shoot objects within 200mm of the optical system. I think the focal length on the lens is more a unit to identify the angle of view. The larger the focal length, the smaller the viewing angle and the larger the magnification.

Honestly, landlord, don't you think I am? For half a photographer, I don't even know what the flange distance is. . . I looked up a lot of information and gained a lot of knowledge myself.