When I presoak Ilford Pan F+ 120 and dump out the water, it's inky-black...why?

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On the last two rolls of Ilford Pan F+ 120 I developed, I presoaked the negatives for a couple of minutes because I thought I had been having problems with uneven development. I was using stainless steel tanks and reels. The first time I dumped out the presoak water and saw that it had a black, inky look to it, I thought I had mistakenly rolled the paper backing onto the reel with the film, and continued to develop normally. I found out that this was not the case, though. Whenever I develop Pan F+ without presoaking, the developer doesn't look very discolored when I dump it out. This phenomenon doesn't seem to affect the negatives, but I was just curious as to what might be causing it. Any ideas?

-- Scott Flathouse (seflathouse.pampa@celanese.com), August 31, 2000

Answers

Greetings,

What you are seeing is the anti-halation coating being dissolved in your pre-soak. This is the coating put on the back of film to prevent film fogging from light striking the rear of the film.

Regards,

-- Pete Caluori (pcaluori@hotmail.com), August 31, 2000.


The last I heard, Ilford was recommending against a pre-soak for their films due to a PhotoFlo-like agent in the emulsion that is supposed to promote even development. That might be another reason for the water's strange look.

-- Brian Hinther (BrianH@sd314.k12.id.us), September 01, 2000.

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