Negative Defect From Washer

[Michael Przybyla]

I wash my 8x10 negatives in a Paterson Auto Print Washer and I am getting what looks like shadows from the plastic dividers. These show up as density differences in areas of sky. Film is HP5 developed in PyrocatHD 1:1:100, processed in trays, fixed in Hypam for 4 minutes, rinsed, and then washed for 30+ minutes. Water is from a well. Print washer is also used for washing silver and Pt/Pd prints so some sort of cross-contamination may be an issue.

My 5x7s processed the same way, but washed in a real dedicated film washer have no issues.

Any ideas on what is causing this and any hope of using the negatives?

Thanks.

Mike

[Jim Noel]

I believe you are correct when you mention cross contamination. I know of no way to prevent this other than using a different method for washing the film. A series of baths in a tray works well. fil a tray with water, shuffle through the negs 2 or 3 times for a minute. Replace the water and repeat. Do this five (5) times should wash even better than the Paterson washer.

[Doremus Scudder]

Mike,

I'm just brainstorming here... Doesn't the Paterson auto-washer agitate? If so, that localized turbulence might be affecting stain formation somewhat (you did say you used Pyrocat). Have you tried the washer in non-agitation mode?

I can't think of a cross contamination issue offhand, but if there were contamination, why would it be regular, i.e., aligned with the slots in the dividers in your washer?

Is it a development issue that just looks like a washing issue? I'm thinking of ribs or ridges on the bottom of the developing tray and emulsion-side-down development. I've had regular areas of increased density in the pattern of the tray ridges when I tried face-down developing and a staining developer. I switched back to face up.

Good luck finding your problem; 8x10 negs are a shame to waste.

BTW, you might try leaving one of your striped negs in the sunlight for a while and see if the stripes bleach away with exposure to UV... worth a try anyway.

Best,

Doremus

[Michael Przybyla]

Jim and Doremus,

Thanks for the suggestions. I think Doremus is onto something on the agitation in the washer. I've washed negatives in the unit before without a problem and since the agitation is essentially powered by the water flow which is hard to adjust, I may have had the flow low enough in those cases so the units was still. Its still surprising since I thought the stain would be more stable after fixing.

Mike

[BarryS]

I've never heard of density variations due to washing. I've been using Pyrocat HD for for a long time and the stain seems completely stable after fixing is complete. I'd bet anything the problem is happening during development. Are you saying the negatives look perfectly even before washing and you see a pattern that exactly matches the divider patterns after washing? What kind of fixer are you using--an alkaline fixer like TF-4 is usually recommended for pyro negs.

[Andrew O'Neill]

wash my 8x10 negatives in a Paterson Auto Print Washer and I am getting what looks like shadows from the plastic dividers. These show up as density differences in areas of sky.

I've noticed this when I leave the negative to sit in a tray with grooves. I can see a ghost image (variation of density) of the tray's grooves on the negative. Doesn't matter which developer I used (main developer is pyrocat-hd) or fixer for that matter as the ghost image is on the film base. Flat-bottomed trays eliminates this.
It would help if you post an example...

[Michael Przybyla]

Here's a sample.

[Light Guru]

Here's a sample.

Those look like groves from a tray during development. What size tray are you using to develop? Perhaps your tray is two small to allow for proper chemical movement.

[Doremus Scudder]

If you compare the shape of the groove-"shadow" on your negative to your washer dividers and your trays, I think you'll find the culprit. For me, the negative defects do not look like the washer dividers, which would make marks that run the other way, or at least without a curved profile.

Take a look at your tray and, like I said before, if you are developing emulsion-side-down, then switch to emulsion-side-up.

Other places to look: stray light during fixing, especially if you are using an alkaline fixer, which can reactivate the carried-over developer even if you use a stop bath (don't ask me how I know this...). Also, the stain is not as stable as many believe until after processing, and even then, stained negatives should be protected from light. With that in mind, be sure you aren't letting the neg sit in anything with grooves the shape of the marks on the neg. Impurities in the final rinse/holding tray/photoflo tray water may remove some stain (I know that sulfite certainly will remove the stain).

And, back to the washer just in case it is the washing: make sure your negs are not sticking to the dividers during washing. This could also cause some unevenness, since the stain continues to form in the wash.

Again, good luck finding your problem.

Doremus

[Michael Przybyla]

Thanks for all the suggestions on the possible culprit. It seems to point to the washer and the agitation. I develop emulsion side up and in a smooth bottom tray that is significantly larger than the negative. In addition, on one negative which was horizontal rather than vertical in the washer, the shadowing was aligned with the washer dividers. I think the washer will work as long as it doesn't agitate.

Mike