DoF may not exist...

Started 2 months ago | Discussions thread
JimKasson
MOD JimKasson Forum Pro • Posts: 34,787
Re: The missing experiment

Erik Kaffehr wrote:

Hi,

I tried to do the experiment Jim was suggesting.

This is a different, but related, experiment. The CoC I chose for the 45mm at f/5.6 at 100 meters was based on using the lens at close to its best aperture.

If the criterion is difference between in-focus parts and OOF parts of the image at the taking aperture, then the allowable CoC has to grow as the lens is stopped down past the best aperture. I suggest the same diameter as the encircled energy 70% diffraction solid.

Note that this is not my preferred metric for DOF at all, but I don't judge DOF at 100% on a monitor; I judge it in the prints, and for that a somewhat more relaxed CoC is appropriate. But this seems to be Greg's standard, and I'm trying to find something that will work for him.

At f/5.6, here are the relevant DOF calculator shots:

There should be no noticeable loss in sharpness at 100 m.

The 29 meter subject will be noticeably soft at 1:1.

-- hide signature --
 JimKasson's gear list:JimKasson's gear list
Nikon Z7 Fujifilm GFX 100 Sony a7R IV Sony a9 II +1 more
Post (hide subjects) Posted by
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
MOD JimKasson
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow