Somewhere in my magazine collection there is an article by this name. I can't locate it. Does anyone know magazine/issue for this? TIA, njb

-- Nacio Brown (njb@sirius.com), September 05, 1999

Answers

It was in Photo Techniques / Darkroom & Creative Camera Techniques, plus I think it was in one of the special B&W issues. No idea what specific issue though. Also online here: http://members.aol.com:/workshops5/prilclct.htm

-- John Hicks / John's Camera Shop (jbh@magicnet.net), September 05, 1999.

Thanks, John. njb

-- Nacio Brown (njb@sirius.com), September 05, 1999.

What a fascinating collection of articles. Thanks for pointing it out.

-- Alan Gibson (Alan.Gibson@technologist.com), September 08, 1999.

Interesting articles, but I take issue with his claim in"Primacy of Local Contrast" that local contrast does not inrease with development time. In his Fig. 2, density curves start at about the same place at the shadow end for various development times and end up in different places at the highlight end, as one would expect: development time affects highlight density much more than shadow density. Assuming these are continuous lines, and they certainly better be, then their slopes must vary SOMEWHERE for them to diverge. His curves show a "bump" just above the shadow end for the higher development times and the slopes of the lines becoming equal again at the higher end. His claim would be true if H-D curves really looked this way, but the curves I've seen don't. The curves I've seen show slope (and thus local contrast) increasing across the range. But, hey, whatever works for you.

-- Tim Brown (brownt@ase.com), September 09, 1999.

Yes, I take issue with a number of things (although I haven't fully digested the papers yet). However, they provide methods for treating overall and local contrast independantly of each other (for example, if you need to increase local contrast while reaining normal overall contrast). I have tended to do this with split-graded printing, but the author provides methods for dealing with it with film processing techniques.

-- Alan Gibson (Alan.Gibson@technologist.com), September 10, 1999.

I believe you are referring to an article by David Kachel in Darkroom and Creative Camera Techniques (July/August, 1991). There are some interesting correlations with William Mortensen's concept of local tone. See my article "Mortensen Revisited" at http://unblinkingeye.com/Articles/Mortensen/mortensen.html.

-- Ed Buffaloe (edbuffaloe@unblinkingeye.com), September 13, 1999.