Please correct me if I am wrong-PyroCat Stain question

[mark]

Probably a dumb thought but here it goes anyway.

This is my thinking: you get more stain with more agitation and less with less agitation. There seems to be a distinct difference in the amount of stain on the negs I processed in trays and those I do in the Unicolor drum. Is this true, and does it have something to do with oxidation? Is it necessarily a bad thing to have more stain?

Random thoughts after a super stressful meeting. I hate managing adults. My sixth graders are more mature.

 

[Jorge]

Probably a dumb thought but here it goes anyway.

This is my thinking: you get more stain with more agitation and less with less agitation. There seems to be a distinct difference in the amount of stain on the negs I processed in trays and those I do in the Unicolor drum. Is this true, and does it have something to do with oxidation? Is it necessarily a bad thing to have more stain?

Random thoughts after a super stressful meeting. I hate managing adults. My sixth graders are more mature.

You are correct, constant and/or roatry agitation produces more stain than shuffling. Having said that, pyrocat should not give you a lot of general stain either way. I process my 8x10 in tubes and I see a moderate amount of general stain, certainly nothing heavy like a PMK or WD2D.

It is not necessarily a bad thing to have more genral stain, in some cases it might even be useful. So dont fret, you are getting the expected results.

 

[mark]

SO how do I avoid the extra staining when rotary processing? Or is it not possible? My exposure times for POP are in the twenty minute range under a 1000 watt HID bulb in one of the top reflectors on the hydroponics market. I know these are excessive times and I want to reduce them while maintaining the density range needed for the process.

 

[Jorge]

SO how do I avoid the extra staining when rotary processing? Or is it not possible? My exposure times for POP are in the twenty minute range under a 1000 watt HID bulb in one of the top reflectors on the hydroponics market. I know these are excessive times and I want to reduce them while maintaining the density range needed for the process.

I think your problem is not in the overall stain per se, but in the exposure/development. Using Pyrocat for pt/pd I would say my negatives are on the dense side, yet rarely do I have a printing time greater than 10 mins. Do this, next time "underexpose" by 1/2 a stop or even 1 stop and keep your development times as they are. I think you will see a definite improvement in printing time with correct detail.

 

[mark]

Thanks. Never thought of that.

 

[sanking]

Probably a dumb thought but here it goes anyway.

This is my thinking: you get more stain with more agitation and less with less agitation. There seems to be a distinct difference in the amount of stain on the negs I processed in trays and those I do in the Unicolor drum. Is this true, and does it have something to do with oxidation? Is it necessarily a bad thing to have more stain?

What you may want to consider with rotary processing is to use slightly more of the A solution than B when mixing the working developer. Say, instead of a 1:1:100 dilution try 1.5:1:100, or instead of 2:2:100 try 3:2:100. The extra A will delay oxidation and reduce stain slightly.

I do not consider this remedy necessary for regular silver gelatin printing, where develoment times for your negatives are fairly short. However, for alternative processes that require a high negative CI, the long devlopment times may give more stain than desirable, especially with thick emulsion and high speed films.

Sandy

 

[mark]

Sandy
COnsidering that I am developing for the higher CI I will try your remedy. Thanks.

Jorge
What dilution of Pyrocat are you using or are you not using pyrocat?

 

[Jorge]

Sandy
COnsidering that I am developing for the higher CI I will try your remedy. Thanks.

Jorge
What dilution of Pyrocat are you using or are you not using pyrocat?

I use pyrocat at 2:2:100 for pt/pd.

 

[mark]

Thanks.

 

[photomc]

Additional ? About Stain

OK, developed first Pyrocat negatives this weekend using Efke PL100 (5x7) rated at 50, processed in Beseler Tubes on a motor - dil. was 2+2+100 for 20 minutes on one negative (N dev.), the other was 2+2+100 for 30 min (N+ dev. for contrast scene was only 3 zones at most). The normal negative does have quite a bit of stain but looks very good (the negative has a problem with light leak from the holder - light trap is leaky) the other negative has obvious (heavy) stain, but it is a very nice looking negative - I mean the negative pops..posted a Ziatype and negative scan from the negative in the gallery.

Problem I found is the zia took forever to print with the Pyrocat negative (becuase of the stain?), while I also processed a 2nd negative using Rodinal 1+50 which prints in maybe 6 min, while the Pyrocat negative went for over 30 min.

Any thoughts (other than maybe under expose, developed too long?

 

[Jorge]

OK, developed first Pyrocat negatives this weekend using Efke PL100 (5x7) rated at 50, processed in Beseler Tubes on a motor - dil. was 2+2+100 for 20 minutes on one negative (N dev.), the other was 2+2+100 for 30 min (N+ dev. for contrast scene was only 3 zones at most). The normal negative does have quite a bit of stain but looks very good (the negative has a problem with light leak from the holder - light trap is leaky) the other negative has obvious (heavy) stain, but it is a very nice looking negative - I mean the negative pops..posted a Ziatype and negative scan from the negative in the gallery.

Problem I found is the zia took forever to print with the Pyrocat negative (becuase of the stain?), while I also processed a 2nd negative using Rodinal 1+50 which prints in maybe 6 min, while the Pyrocat negative went for over 30 min.

Any thoughts (other than maybe under expose, developed too long?

King designed Pyrocat HD to have a greater actinic blocking response than "normal" developers. This is why many of us use densitometers that can read UV density, the UV blocking properties of Pyrocat HD can be as high as 2 stops more than those read with a Visible chanel and it is not susprise that if you got a negative that looks dense with pyrocat that it took too long to print.

IMO 20 minutes with a 2:2:100 dilution is a bit much if you want to go shoot for n+1, I would use about 16 minutes.

 

[John Z.]

Another way to reduce stain is to add more sulfite, which greatly reduces stain. Sulfite can affect developer in other ways, so titrate slowly. One lesson here is that different methods of development can yield greatly different stain patterns, and the negatives are much different. Additives like Amidol, Metol, and Pyro can greatly increase stain levels as well, for better or worse.

 

[photomc]

Back home now and looking at the negative, think I may have found part of the issue..which I know if possible with Pyrocat...looks like I have quite a bit of dichronic fog (think that's the correct term). The emulsion side has a rather different sheen to it when I hold it at a right angle to the light. The shorter development time is not as remarkable, but there none the less. Will reshoot and try again...with shorter times.