pyrocat hd problem

[mike fitzgibbon]

I have used pyrocat hd about three times with success and the last two times my negitives came out clear. I use a combi tank for 4x5 pre soak film for 2min semi stand
at 16 min. Pyrocat mixed at 10-10-100 at 70 degrees plain water stop and ilford rapid fix for 12 min. Agitation is at every 4min. This last time around I started with new
pyrocat stock from formulary as I thought I may have cross contaminated A and B.
Any thoughts would be appreciated.

[Colin Graham]

Clear negatives...I'm assuming you mean to write 1-1-100 and not 10-10-100, but even if not I think that would have made bulletproof negs and not clear ones, even 1-1-100 is strong for semi-stand. A 12 minute fix seems very long, but whether it's long enough to clear the neg entirely I'm not sure. This is the same batch as used with the successes?

[Jorge Gasteazoro]

I have used pyrocat hd about three times with success and the last two times my negitives came out clear. I use a combi tank for 4x5 pre soak film for 2min semi stand
at 16 min. Pyrocat mixed at 10-10-100 at 70 degrees plain water stop and ilford rapid fix for 12 min. Agitation is at every 4min. This last time around I started with new
pyrocat stock from formulary as I thought I may have cross contaminated A and B.
Any thoughts would be appreciated.

Rapid fix for 12 minutes?!? I would say this is your problem right there, you are dissolving even the reduced silver. Depending on the film, rapid fix shoul dbe used from 2 to 4 minutes at the most. Most likely in your previous trials you had a somewhat exhausted fixer and this is why you got results, if you used fresh fixer this time and left it for this long I am not susprised you got a blank negative.

[Brian Ellis]

Can you see the writing (brand, type) on the edge of the film? If so then the problem most likely wasn't with the processing, it was with the exposure. If you can't even see the writing on the edge of the film then the problem most likely was with the processing. Exactly where in either case may be difficult to figure out but it at least gets you started on the right track.

As an aside, where did you get your 12 minute fix time? I don't think fixing for that length of time would cause a totally clear negative but IIRC when I was using an Ilford fix their recommended time was 1 or 2 minutes (I don't remember whether I used Rapid Fix or not, I may have used another kind of Ilford fix).

[scott_6029]

Make sure you have not contaminated in any way bottle b with a - or, how old is your pyro hd? If too old then both of these will result in extremely thin negatives.

[scott_6029]

hmmm. Sorry, didn't see post on fresh chems, no contamination...regardless you are fixing too long...but I can't see this resulting in totally clear....sounds like an exposure problem, like quick loads inserted backwards...yes, we have all done this at one time or another...

[Greg Nelson]

This happened to me once, too. I had used Pyrocat HD with great success on HP5+ and FP4 LF film, and once I used it on 5 120 rolls of Ilford Delta 400 -- all clear! Pretty spooky. Never did figure out what happened, but decided that I must have grabbed the "A" bottle twice and left out the "B". I've been afraid to try it on Delta 400 again, though. What film were you using?