question about salt prints

[glbeas]

Given that a salt print is a POP type process with a fairly long exposure, has anyone ever tried to run a salt print through a developer? Would this result in a much higher sensitivity or does it merely develop all the silver indiscriminately? I tried a scrap in some Dektol but it turned all black, but I don't know if that was because of over exposure for developing out or another problem.

 

[glbeas]

Okay I've come up with another question. I made a nice looking print, rinsed, in the fixer where it faded considerably, hypo clearing bath then into the wash. At that point the print started fogging in the highlights, a chemical fog as I was under a red safelight the entire time. Any suggestions as to improving the performance here?
Paper was Arches Aquarelle, 3% NaCl and 12% AgNO3.

 

[smieglitz]

Gary,

I'm not sure if you are referring to processing that print as a regular salted POP or trying to develop it, but, with the regular POP process you need to tone the print with a gold or platinum/palladium toner formula before the fixing step. Otherwise the print will bleach considerably in the fixer as you describe. Also, the fixer for POP processes is generally much weaker than conventional silver gelatin process fixers. Rapid fixers are out as is toning with Kodak Rapid Selenium Toner which is compounded with high percentage of ammonium thiosulfate aka rapid fix. Weak solutions of sodium thiosulfate aka "hypo" are generally used for the silver alternative processes. Hypo solution strengths are generally around the 2% mark although sometimes the strength is higher (I've seen it up to 15%) and sodium carbonate is added to the plain hypo fixing bath to make it alkaline in order to reduce the bleaching problem.

Don't know about the after process fogging. Was the clearing agent Kodak Hypo Clearing Agent (primarily sodium sulfite) or something else?

IIRC, another thing to try is adding some table salt to the initial rinse. This apparently helps remove the excess unexposed silver. Before trying this or the alkaline fixer though I would try to find a reference either on the web or in a standard alternative process text to determine the strength and duration needed.

You might also try a different paper for salt printing and other processes. I've found Arches Aquarelle to be inconsistent and prone to uneveness with alternative photographic processes. Give Cranes' Cover, Kid Finish, or one of the better Bristol papers a shot with salted paper.

Joe

 

[paul1287]

Check out the book "Primitive Photography for detailed info on developed-out salt prints. Yes, you ned less exposure and even less sensitizer but it requires some extra chems to get the job done and the result is not as warm a print as a printed-out salt print.

 

[glbeas]

Thanks for the tips. I was using a 5% thiosulfate with .1% sodium carbonate as per directions I got off the web. May need more carbonate as it bleached back as fast as the diluted rapid fix I tried at first. The clearing bath was Heico Permawash, which might have something to do with the fogging, I'll have to try straight sulfite and see what happens. I'll definitely try the salt rinse.

If I can find a copy of Primitive Photography I'll definitely grab it. You know offhand what extra chems are needed and how they are used?

 

[Ole]

Thanks for the tips. I was using a 5% thiosulfate with .1% sodium carbonate as per directions I got off the web. May need more carbonate as it bleached back as fast as the diluted rapid fix I tried at first.

Why Carbonate? I have used sodium thiosulfate alone with good results, and mine is mixed with acidic water.

Some of the "bleaching back" observed in the fixing is a temporary lightening, it will get darker as it dries.

Toning before or after fixing gives me the same end result, but toning is much slower after fixing.

Skip the hypo clearing bath - it shouldn't be needed, so it's just another complicating step.