overall stain(?) on negative

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I've been experimenting with getting pictorial gradation from lith film using various developers. The other day I used the metol-glycin FX2 (but it uses metaborate instead of carbonate as the alkali). The film has a curious yellow-orange stain. My first thought was aeriel fog but the unexposed edges of the film (which were covered by the sheet film holder) were clear without any trace of the stain. I haven't actually printed any of the negatives yet to see if the stain is proportional to density (and lack a color densitometer to see if that is the case). But I'm curious as to whats happening with the chemistry here - I'm pretty sure glycin is supposed to be a pretty clean working developer and resistant to aeriel fog. I've used diluted D23 (metol based) before and that was pretty clean. Any hunches what I'm seeing here? Thank. DJ

-- N Dhananjay (ndhanu@umich.edu), January 26, 2001

Answers

The only thing I can think of is that maybe the glycin had oxidized too much. How old is the mixture and how old is the glycin you mixed the formula with? You probably know that fresh glycin is almost white, but that it darkens steadily as it ages.

I should think that the use of metaborate instead of carbonate would have reduced the activity rather than increased it, but it would have held the pH steady throughout, whereas with the carbonate it would have dwindled over time--this might have given more activity over the long run.

-- Ed Buffaloe (edb@unblinkingeye.com), January 26, 2001.


Thanks for the reply, Ed. The stock was prepared maybe 2 months ago (with fresh glycin) and the working solution was mixed just before processing. I'm inclined to rule out oxidized developer in the stock because I made some working solution about a week earlier to develop some regular film and it worked fine. Also, the edges of the film (which had received absolutely no exposure) did not show any stain. I'm guessing oxidized developer would have led to general (i.e., not image specific) stain much like fog. Cheers, DJ.

-- N Dhananjay (ndhanu@umich.edu), January 27, 2001.

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