eumenius
Member
Hello friends,
my story with P-C-Soda developer continues... while trying to develop another roll of 120 type Foma 100 in a developer mixed from dry ascorbic acid, sodium carbonate stock and phenidone solution, I got heavily underdeveloped negatives, though I developed the film in full accordance with my experimentally obtained times! What the *&^%, thought I. Everyone uses this mix, with no such unstability. My education, however (I was one the enzymologist, working with enzyme kinetics), told me somehow that there could exist a kinetically limited phase of the developer activation - say, ascorbic acid relatively slowly forms some transient-state intermediate that is active photographically. I set up an experiment that way: I mixed my developer and let it stand on the table for 45 minutes in beaker. Then I developed a film with it. Result: a good negative with too much of a density, maybe I should develop it for 8 minutes instead of 10. Also I noticed some streaks from uneven development, even when I put the loaded reel in prefilled tank in an instant. The presoaking of the film is required, perhaps - at least in Fomapan case.
I will write more about my experiments, so my new information will help people to use Gainer system more effectively on a different films.
Regards from Moscow,
Zhenya
my story with P-C-Soda developer continues... while trying to develop another roll of 120 type Foma 100 in a developer mixed from dry ascorbic acid, sodium carbonate stock and phenidone solution, I got heavily underdeveloped negatives, though I developed the film in full accordance with my experimentally obtained times! What the *&^%, thought I. Everyone uses this mix, with no such unstability. My education, however (I was one the enzymologist, working with enzyme kinetics), told me somehow that there could exist a kinetically limited phase of the developer activation - say, ascorbic acid relatively slowly forms some transient-state intermediate that is active photographically. I set up an experiment that way: I mixed my developer and let it stand on the table for 45 minutes in beaker. Then I developed a film with it. Result: a good negative with too much of a density, maybe I should develop it for 8 minutes instead of 10. Also I noticed some streaks from uneven development, even when I put the loaded reel in prefilled tank in an instant. The presoaking of the film is required, perhaps - at least in Fomapan case.
I will write more about my experiments, so my new information will help people to use Gainer system more effectively on a different films.
Regards from Moscow,
Zhenya