What questions should I ask about photography?

In other words, do you want to know how big the aperture corresponds to how big the depth of field is, this quantitative calculation?

First of all, we should understand a basic concept, that is, the factors that affect the depth of field are not just the aperture.

The definition of depth of field is the size of the clear range before and after the focus. So what is "clarity"? The concept of allowable dispersion circle is introduced here. You don't need to know the details of this concept. In short, it is to quantify the limit that the naked eye can distinguish when you enlarge the photo to a normal size, that is, how to be "clear", so as to measure the degree of the "clear range" mentioned above. The main factor that affects the size of the allowable dispersion circle is the frame of the camera.

Then there is the problem of imaging level. Depth of field is also related to aperture (aperture), lens focal length and object distance (distance from camera to scene).

So the formula exists naturally and is not too complicated:

If you feel troublesome, there are depth of field calculator software, computer program version, web page version, and mobile APP version. ...

However, I don't think it is necessary to be so digital in general. Photography is a thing. Perception is more important than reason, or feeling is more important.