Ask two simple questions about photography (which may involve microphotography)

Ask two simple questions about photography (which may involve microphotography)

Reward points: 150- 13 days. The question ended 22 hours ago.

1, what is the function of aperture and numerical aperture? What does it have to do with resolution, depth of field or depth of focus?

2. What is the relationship between the focal length of the lens and the shooting range and the size of the object image?