Is he missing the point with this video?

[Mainecoonmaniac]

I think this YouTuber really knows is stuff and I learned quite a bit from him. I think he's one of those Millennials that never shot film. In the video, he compares the depth of fiend between an LF camera and a DSLR. He was gushing about how the 4x5 shots looked and how shallow the DOF is. Is he really talking about the shallow and the look of film? This posting is not hating on him, but just a comment that some young photographers are rediscovering film. Correct me if I'm wrong.

 

[scheimfluger_77]

I’m not sure where he gets the idea that f/4 on LF is equal to f/1 on full frame digital. I’ve never heard that. The big difference is how the lens renders the unsharp areas, we all know this of course. Also I expect the the lens on the digital was not the same fl as the 4x5, there’s another part of the difference. Again we all know this but he may not. I think what he’s seeing is the not the difference between the format sizes but the unique lens characteristics of each.

 

[John Koehrer]

I've no idea how he determines his aperture/focal length equivalents for this. Film area vs sensor area maybe?
Graphic Graflex Photography from 50-60 years ago says that you get the same DOF for a given PHYSICAL diameter
not f number. This had no relation to focal length. Can't find the book on my shelf anymore and can't give a reference
beyond the title.

 

[AgX]

I’m not sure where he gets the idea that f/4 on LF is equal to f/1 on full frame digital

Not F4 but F2.8

F2.8 at 4x5" equals F1.0 at 35mm


(I did the calculation for COC of 0.1mm at 4x5" and 0.3mm at 35mm, and 150mm resp. 50mm FL)

 

[MattKing]

Graphic Graflex Photography from 50-60 years ago says that you get the same DOF for a given PHYSICAL diameter not f number. This had no relation to focal length.

Well, I wouldn't exactly say "no relation" ....
The physical diameter and the focal length and the f/number are all related to each other, using a well known equation - f/stop = focal length/aperture diameter (IIRC) .
I expect what you are saying is that the DOF is determined by the physical aperture and the subject distance (and the Circle of Confusion you find acceptable). To calculate equivalencies, you need to solve that equation using the same physical diameter.