Depth of Field on the D800E

[Shashin]

In the same spirit, here's another question to ponder: what does sharpening do to focus transitions, and to our subjective perceptions of DOF?

Tricky question. Our perception of DoF is really complex and subtle. Sharpening should impact the DoF as it would impact acceptable sharpness. What the practical result would be is harder to quantify. I would say it is insignificant, simply because a high contrast scene would be "sharper" than a low contrast one and I don't think we perceive changes to DoF because of increased contrast. At least in any practical measure.

 

[Oren Grad]

Tricky question. Our perception of DoF is really complex and subtle. Sharpening should impact the DoF as it would impact acceptable sharpness. What the practical result would be is harder to quantify. I would say it is insignificant, simply because a high contrast scene would be "sharper" than a low contrast one and I don't think we perceive changes to DoF because of increased contrast. At least in any practical measure.

I'm not sure there is a hard-and-fast answer, given the strong role of subjective perception and the huge variation in image content and in sharpening practices. I mentioned it here only because in trying to understand the phenomenon that induced Roger to launch this thread, I don't think it can all be boiled down to picking the "right" CoC to plug into the classical formula.

 

[Shashin]

I don't think it can all be boiled down to picking the "right" CoC to plug into the classical formula.

Sure it can. DoF scales and calculators are only a guide that lets you visualize the DoF in a scene. You can even make your own CoC if that gives you a better way to see it--I know a few folks that choose the DoF index one stop open than the set aperture because they find it meets their expectations better.

I don't think basing DoF for 100% monitor view is very useful, unless you crop a lot.

 

[Jan Brittenson]

Sure it can. DoF scales and calculators are only a guide that lets you visualize the DoF in a scene. You can even make your own CoC if that gives you a better way to see it--I know a few folks that choose the DoF index one stop open than the set aperture because they find it meets their expectations better.

Knowing what you get at certain stops on the scale is just a matter of getting acquainted with the equipment. It doesn't matter if it's perfect as long as it's consistent, meaning it's pretty easy to stop down one or two stops extra vs what the scale says. Not only that, but because the scale is consistent it's pretty easy to directly map that value to a diffraction-optimal one. It turns out the crossover between stopping down and diffraction is purely f-stop related, and unaffected by focal length. Here's the scale I had taped onto my Mamiya 7:

Basically, if the lens scale says f/5.6, stop down to f/16. But this is on 6x7; on 35mm f/5.6 would map to f/8-11 approximately. Maybe f/8.5. (.5 indicating a half-stop, so effectively f/11)

But it really comes down to knowing the equipment and how to use it effectively.

Unfortunately the DoF scales on modern lenses suck.

Of course, this assumes a lens that doesn't need to be stopped down further to perform. Those sometimes have their places as well, but in that case I'd just stop down the lens to f/11 or whatever it needs to do well.

 

[waynelake]

I met someone who did that too. Would use depth of field scale, focus for f8 and take picture at f11, as an example.

 

[GrahamWelland]

I've been doing this with digital for years. I use 1.5 - 2 stops off the film indicated hyperfocal - something I also got used to from my Mamiya 7 days (and that was on film too!)