Re: re-clearing pt/pd
I would say it depends on the type of stain; or yellowing. I have very successfully cleared prints after they were dried and this was sometimes many days after the first printing. I have used any of the standard "silver" clearing baths like Kodak's Hypo Clear Agent or Heico Hypo clear. I have also done additional clearing with Sodium Sulfite and EDTA mixes or home brews of HCA.
There are of course some stains that simple clearing will NOT be able to clear. Depending on how dear that print is and where on teh paper the stain, Bleach - like Clorox will whiten the stain, but may also REALLY screw up the paper so great care needs to be taken if you go down that path.
The type of stain might indicate whether a strong amount of EDTA or sodium sulfite is needed.
Any of teh standard acids may also be tried; HCL, oxalic and phosphoric Acid. These may require a bath of sodium carbonate after to help heal the paper from long term acid burn. This is what I'll call the residual effect of an acidic bais left over from the acid bath.
Eric
From: Dan Burkholder <fdanb@aol.com> To: alt-photo-process-l@usask.ca Sent: Wednesday, December 17, 2008 9:32:12 PM Subject: Re: re-clearing pt/pd For the longest time I thought that you could not clear a dried and yellowed print. But at least for Bergger Cot 320, a second (post dry) clearing in Hypo Clear did indeed take the yellow out in a workshop in which the local water was causing insufficient clearing in "other" clearing agents. Best of success!
Dan
On Dec 17, 2008, at 5:05 PM, Paul Viapiano wrote:
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