Quote Originally Posted by albada View Post
So I learned that PG + sodium metaborate + ascorbic acid can crystallize. The Dimezone S seems to encourage and/or cause it though. So I think something other than hydrolysis is happening.
This is just a simple theory based on lack of knowledge, but could it be that the precipitate is oxidized ascorbate?

Here is what hints in that direction:
  1. Oxidized products of ascorbate have no distinct color, i.e. you don't see when it happens in water.
  2. We know that Phenidone/Dimezone S catalyzes oxidation of ascorbate, that's why it is superadditive
  3. We know that this happens more likely in caustic environment, hence you see it faster with metaborate

A very quick'n'dirty test would be, of course, if you would try developing a test clip of film with the soup once it precipitates.

Quote Originally Posted by albada View Post
And the density-curves comparing it with XTOL:
I've never seen such close graphs. The grain looks the same as XTOL under close exam on the light-table with 22X loupes.
I would like to know to which extent variations in composition have a visible effect on characteristic courve, grain, sharpness, etc. Since you have obviously done lots of experiments before you came up with your final result, could you comment on that? Would a 10% variation make a big difference or does it take much more before you saw anything different?