Wait what? I’m not so good at math, which is why I write words and take photos for a living, so not really following this video. But because the narrator, John Hess, has equations and seems to know what he’s talking about, I believe him that a smaller sensor has shallower depth of field
From the video’s description:
How much space in front of the lens will be in focus? That question defines Depth of Field – but this simple concept has lead to a staggering amount of confusion in today’s multi-format camera environment. Through some fundamental scientific demonstrations, we will clarify concepts like circle of confusion and lens equivalency.
Watched the video a few times now and still deep in the Circle of Confusion with lens equivalency, but giving it another go with coffee in the morning and a good nights sleep. I think it means, to get the same DOF with a cropped sensor, as a full-frame sensor, the subject needs to be further away.
I think.