RE: pH question
DEAR ERIC, Thanks! I was thinking that, the best thing to do would be to measure the pH of the newly mixed Sodium Citrate (I accidentally said Pot Cit in my original e-mail) dev which we know works well. Assuming it should be below 7 I can keep it at or slightly below that pH by adding citric acid. CHEERS! BOB -----Original Message----- From: EJN Photo [mailto:ejnphoto@sbcglobal.net] Sent: Tuesday, March 20, 2007 2:41 PM To: alt-photo-process-l@usask.ca Subject: RE: pH question Bob, I'd go with Don on this. Nadeau recommends that it be kept acid; below 7. He doesn't give a low end. I don't seem to be able to lay my hand on Stevens Kallitype book right now, but If I do, I let you know. One way to do it without a reference would be to check it now and again, and track the changes. When it is at or close to 7 add citric acid to reduce it to 6. Make a print and see how it looks, then make an additional drop in pH perhaps to 5.5 and see what happens with an additional test print/wedge. I believe it is just that it likes acid environment, but no need to get it too low. Eric Neilsen Photography 4101 Commerce Street, Suite 9 Dallas, TX 75226 214-827-8301 http://ericneilsenphotography.com Skype : ejprinter> -----Original Message----- > From: BOB KISS [mailto:bobkiss@caribsurf.com] > Sent: Tuesday, March 20, 2007 12:06 PM > To: alt-photo-process-l@usask.ca > Subject: RE: pH question > > Anyone??? > CHEERS! > BOB > > -----Original Message----- > From: BOB KISS [mailto:bobkiss@caribsurf.com] > Sent: Tuesday, March 20, 2007 9:17 AM > To: alt-photo-process-l@usask.ca > Subject: pH question > > DEAR LIST, > At what pH should I keep my Potassium Citrate developer for > pt/pd? > Eric Neilson suggested that I keep my Pot Ox dev at between > 5 and > 5.5 with small additions of oxalic acid when necessary. I can > add small > amounts of citric acid to my Pot Cit dev but I am hoping to > know what the > best aim pH is for best development. > Thanks in advance... > CHEERS! > BOB > > Please check my website: http://www.bobkiss.com/ > > "Live as if you are going to die tomorrow. Learn as if you are > going to > live forever". Mahatma Gandhi > > >
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