Question

In order for a film camera with a fixed focal length F to focus on anobject located a distance x from the lens, the lens must be a distance yfrom the film. F, y, and x are related as follows:

Now suppose a camera has a lens with focal length F = 65.

Explain what happens to the distance between the lens and the film as the object moves far away from the lens. When an object far away (x is near infinity), what is the internal distance from the lens and film?

Consider the opposite. Explain what happens to the distance between the lens and the film as the object moves closer and closer to the lens. Is there a distance from the lens at which you can no longer focus?

In general, why is it not possible to cross a vertical asymptote?

What is focal length, and how does it work?

Answer 1