Gum, of course, is full of surprises. The other day I got a
wave effect that 48 hours of soaking didn't remove. (One moment of
carelessness -- I put the paper into the water sloppily -- and you have a
whole new bug.) But I could at least construct a theory for that event,
however mistaken it might be.
For what I now describe, I haven't a clue or even a notion. It
happens only with certain brands of watercolor -- never with Rowney, BTW.
(If someone is moved to advise: so use dry pigment, PLEASE, have mercy!)
What happens is that a test under a 21-step shows a nice progression from
dark tones to light to paper white, but, starting at maybe step 13 or 14,
what should continue as paper white becomes stained -- not in clear
steps, but starting pale and usually noticeably darker by step 21.
This has no practical effect on prints, since the actual negative has no
density up in the 13th-step-plus range, but it looks weird and the puzzle
Has anyone else noticed this? Any ideas?