Re: Pyrocat-HD postwashing staining phenomena

From: Sandy King ^lt;sanking@clemson.edu>
Date: 05/19/04-08:01:33 AM Z
Message-id: <a06020424bcd114044118@[192.168.0.2]>

Manuel,

Your description of the film sticking to the net
and causing a pattern is interesting. My own
testing of the amount of stain that is developed
during washing, which indicates very little,
would not have suggested anything like the
phenomenon you have encountered.

That said I am not sure how much help I can offer
you since I have not ever used the 3005 drum or
the net apparatus you describe. But here is what
I would do.

1. Load the film wet and pre-soak in regular tap
water, and for good measure you might add a
little carbonate to the water it to make it
alkaline. This will cause maximum swelling of the
gelatin and fast induction.

2. After development use an acetic acid bath to
make sure that you stop development action. It
could be that your wash water is alkaline with
the result being continuing developing action,
especially if for some reason your fixer is weak
or depleted. In other words, the pattern from the
net you describe could be a result of continuing
development, very slight but still enough to
cause a problem.

3. Remove the film from the drums after the
acetic stop bath and fix and wash them in a tray.
This is my procedure with all film that is
developed in tubes and trays and I have never
experienced any problem with streaking or
mottling.

Sandy King

This would be even more likely if your wash water is alkaline.
>Sandy and all Pyrocat-HD afficionados:
>
>
>
>
>I'm getting streaking and mottling with 8x10 FP4 developed in Pyrocat-HD.
>
>The procedures are :
>
>
>Jobo CPP2
>
>-5 minutes water pre-bath in distilled water
>Development at 2:2:100( mixed dist. water),
>73F, slowest rotation possible, Expert 3005
>Drum ,
> 1000ml developer volume, followed by 2 water rinses.
>Fixing with Ilford Rapid Fixer.
>and now is were the problem is ( I suppose )
>happening , at the film washing!
>
>Concerning Rollo and others Pyro developers
>the available literature often refers to the
>stain that develops during the film wash. I
>suppose the same applies to Pyrocat.
>I notice this phenomena after washing sheet
>film in a Kodak N. 3F deep tank equipped with
>a color print processing basket. The dividers
>are made with a very soft fiber glass net. With
>the film dried , I could notice very clearly
>the net pattern of the basket in the sky area .
>
>I think this happened because the emulsion side of the film sticked
>to the net, not allowing a even contact with
>the water. Because of that, the stain developed
>during the washing was more intense in the
>clear areas of the net , producing this pattern
>in the film.
>
>But this is not all.
>Making a feedback to some mottling and streaking
>I had with Pyrocat, I suppose the possible
>reason may be an uneven flow of water during
>the washing time. That results in a stronger
>visible post-washing staning in the areas in
>contact with a more intense flow of water.
>
>Meanwhile I've made the following test:
>After developing one FP4 8x10 with the
>described method , I cut it in half and washed
>the two half negatives with different methods.
>One in the Kodak processing basket and the other
>in an horizontal Kostiner washing tank. The
>results were clearly differen, concerning the
>mottling and streaking patterns .
>
>Do you think the intensity of the water flow has
>influence in the post staining ?
>Can this explain some cases of mottling and streaking ?
>What do you advise for a perfectly even film washing ?
>
>How do you wash your 5x7 or 8x10 or larger sheet film ?
>In vertical archival tanks ?
>In trays with Kodak siphon ?
>
>I look forward to know Sandy opinion and of course of other list members.
>
>Thank you all
>
>
>Manuel Gomes Teixeira
Received on Wed May 19 08:19:57 2004

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