I know I oversimplified a bit. However, what is important to me when print developing is not necessarily reaching maximum contrast, but being able to control the contrast a bit with print developing time. The time between when max black and max contrast are reached is what is interesting in this respect. After max contrast is reached, the paper simply gains in speed, or fogs.
The leeway between max black and max contrast allows one to pull a print a little early and throttle back on the contrast somewhat. As far as I'm concerned, if this is the contrast I'm after, then my print is "done" (although maybe on the rare side...) even though max contrast has not been reached. Sometimes I even pull a print before max black is reached; a couple of prints I have work better with a less-than-maximum black.
Although I am not intimately familiar with Phil Davis' writings on the subject, his approach seems to make perfect sense, especially if one is after repeatability. For me, however, I don't necessarily cook every print the same way. The reason I put the word "completely" in quotes was that its definition is not univocal. Davis has good reasons for calling the shortest time to reach max contrast "completion," however, many of my prints are "complete" before reaching max contrast; my definition being, "with the range of tonalities I desire" rather than any more quantifiable, sensitometric point.
Playing with developer time is one of the variables that makes printing an art for me. There is a "fresh" look to prints pulled early that I just can't duplicate with less exposure and a longer developing time. Although I haven't done densitometer analyses of any of these, I would guess that look is due to the curve shape of the paper being different when it is pulled a bit early as compared to reaching maximum contrast.
At any rate, the OP was concerned with whether too hot would significantly affect his printing; the consensus here seems to be that it will only speed it up, not change the image characteristics of the paper.
Complete Development Requisite
As for myself a sheet of print paper is completely
developed when all of the potential image silver has
finished it's development. That is the requisite for
developing to completion. Anything less is pull
From the one graph Phil Davis included in his article it
can be seen that LESS exposure is needed for maximum
black AND maximum contrast. That is, development to
completion. More exposure and less development can
produce maximum black but at a lower contrast.
For practical purposes to completion processing
is easier to consistently achieve than pulling
early especially if processing times
are short. Dan
Exactly! For most (90%) of my prints I develop to "completion" as you define it. Some prints, however, look better when "pulled." We are just using different terms to say the same thing. When I have a finished print that I am satisfied with, it has been developed "completely" enough for my purposes, even though it was "pulled" before reaching "completion"...
The print exposure/development time variable you mention is often a good tool for refining contrast by small increments. I use graded papers for the most part, and this is a good addition to my contrast-control tool kit.
BTW Dan, can you give me a link or reference to the Phil Davis article you are referring to, I can't seem to find the graph you mention anywhere on the BTZS website. Maybe I'm looking in the wrong place?
I've been working with a Post Exposure Pre Development method
Originally Posted by Doremus Scudder
of Global Contrast Control pioneered by David Kachel. Required is
a post exposure short soak in an extremely dilute potassium
ferricyanide solution. So far I feel a guarded PHENOMENAL
is due. Terrificly good shifts in gradation. Known as
SLIMT I think my handle more descriptive; PEPD.
I know SLIMT will stick.
Volume 7 Issue 4 of the D-Max Newsletter from what was the
View Camera Store. I'm inching towards scanning and posting.
Hopefully I'll be able in a few days to post the article and
some of my PEPD, excuse me, SLIMT results. Dan
I've yet to try the SLIMT method for prints, although I've studied it a bit. However, I now use SLIMT for all my Zone System contractions and am very happy with the results. N-4 with only about a stop loss in film speed. I've heard this can make for grainier negs, but have not had any noticeable problems in that department.
I'm looking forward to reading your PEPD/SLIMT results. Would you mind posting here or PMing me when you put it up?
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