Interesting - thanks for the added info and background as always, Ron.

The tables I wrote out are from Haist. Unfortunately I don't know where I'd be able to get the original research paper, which no doubt would shed some light on certain aspects, although Mr. Bill who responded earlier in the thread seems to have a copy.

So would the acutance measurements you describe indeed factor in edge effects?

What fun I would have doing a rigourous series like this with current films!

Any insight on why the acutance-type formulas in the test gave such poor results with Tri-X - where all three of the triad variables were worse than the baseline (D-76)?

Or why a mushy developer like D-25 would give Panatomic-X the same acutance as D-76 1+1?

By the way apologies again for having to attach my summary as a PDF. When I tried repeatedly to copy the text into the body of the reply, I couldn't get any of the spacing to work properly and the data was impossible to read.