In article , +++ATH0
wrote:

One other factor to bear in mind: the depth of field varies with lens
focal length, not field of view of the subject.

actually, it's aperture.

actually, it's the ratio of focal length to aperture.

nope. depth of field is a function of physical aperture.

what you describe is f/stop, which is used for exposure purposes, and
in some cases (usually movies), t/stops are used, which is actual light
transmission through the lens, not a simple ratio.