Quote Originally Posted by timbo10ca View Post
Will- I guess my confusion was in my incorrect notion that once I exposed past zone 5 or so, the highlights would all expand more or less equally with increased development, thus giving equal density across the board. When I have tried "super development", this seemed to be the case. For example, I did an extreme minimal aggitation of HP5 in a tube for 2 hours in HC-110 dilution B at 24deg C. I was expecting a massive contrast range- it was actually quite low (around log 1.1 using my RH Designs meter in densitometer mode) and had huge amounts of base fog. This shook what I had taken as gospel. I have been told though that dvelopment past a certain point will do this, so I am now wondering where the cut-off should be.
2 hours is quite a long time. You'd be better off with stronger dilutions, shorter developing times, more agitation, or some combination of the three. For starters you could shoot a low contrast scene at normal exposure, +2 stops, +4 stops, and +6 stops. Then give equal development to all sheets, say your normal time plus 20-30%, make prints all at the same paper grade compensating for variation in negative density with changes in exposure time. Then you could easily see the actual effects caused by changes to your initial exposure.

A great book that goes into medium to extended detail on this and other subjects is Bruce Barnbaum's, "Art of Photography" http://www.barnbaum.com/artofphotography.html. I have an older version (somewhere???) but I am sure the new revised version is excellent as well.