>> I think Multigrade is presented strictly as a developer for silver paper,
but using a slow, fine-grained film to produce long scale negs for Pt or POP,
there's a certain logic to using an energetic paper-style developer.
Many of them use high-energy developer with some (or lots of dilution). I
believe the logic is exactly that: high energy with low concentration. On the
shadow areas, we don't need lots of developing agent, so it is sufficient to
develop completely. Moreover, since the developing agent is high-energy, it
develops quickly, thus we have increased shadow contrast or increased shadow
separation.
However, if you just use a high-energy developer, the contrast of the whole
thing will be high and highlights will be blown out. Here is when the dilution
takes action. The highlight needs a lot of developer, but since the developer
is diluted, it gets exhausted quickly (when there is low agitation). The
effect is the development of highlight is slowed down. So highlights are
compressed so they print better.
Some called this action "self-adjusting" (because less exposed area gets more
development but more exposed area gets less development); others call it "self
masking" (because on the macro level it has similar characteristic of a
negative with a mask added although on the micro level they are not the same);
still others call it "compensation" which admittedly is a confusing term.
Dave
PS: To all, if some of my statements in my 3-part message sounded too strong,
I really apologize.