[GiovanniP]

> assuming infinite resolution

this is an assumption that goes against the concept of "f-number" so if one does it, they should not expect to get to anything sensible.

[wvbdmp]

I just meant sensor pixels, because you’re obviously losing those when cropping, but you get the same perspective as from larger focal length (since you’re not moving).

[GiovanniP]

I agree that the images correspond to the same region in object space. Further assumptions on optical resolution don't work well, as the optical resolution depends on the f-number.