RE: Polytoner trouble: black specks
Dan, I don't know about Polytoner but various kinds of chemical contamination cause selenium to precipitate out of selenium toner - as extremely fine black particles that can look reddish. Is there a possibility that the film still contains traces of silver halide when subjected to toning? (i.e. wasn't completely fixed!!) Sorry to ask, but paper prints can be given a good brown tone by bleaching (ferricyanide-bromide, etc.) and then toning in a strong selenium solution - it puts down a fairly heavy, powdery precipitate of elemental selenium (and exhausts pretty rapidly) while doing this, so I thought your problem might be related. [Used to get psychedelic orange/red colours by selenium toning after bleaching with iodine, but don't know if it would still work with modern emulsions.] Liam -----Original Message----- From: Dan Fuller [mailto:dhfuller@wisc.edu] Sent: 18 December 2006 19:44 To: alt-photo-process-l@usask.ca Subject: Polytoner trouble: black specks I am processing b&w 35mm motion picture prints on Eastman Fine Grain Release Positive film which I would like to tone. This is a wonderful, inexpensive, fine grain, blue sensitive film that can be treated much like RC photo paper. In the past, I used Kodak's Polytoner--now discontinued--with good results. I run the prints through a countertop processor designed to develop 100 foot lengths of microfilm (Recordak Prostar). The toning looks good but I am getting tiny dark specks on the emulsion side of the film throughout the 100 foot length. These specks can be removed with water and gentle scrubbing . . . mostly. When observed with a bright light at just the right angle they look metallic, a coppery red. I tone prints that have already been developed, washed and dried. For toning they pass through these stages at 90 degrees F: water wash, 2 tanks of homemade polytoner, water wash, 1 tank of Hypo Clear, water wash, dryer. Each tank of homemade polytoner contains: Part 1: Kodak Rapid Selenium 10 ml Balanced Alkali 20 grams hot water 250 ml Part 2: Liver of Sulfur 20 grams Borax 1 gram hot water 250 ml I mix these and add enough hot water to bring the solution up to 650ml. For my last run, I carefully filtered Part 2 which tends to be sludgy, but I still got the dark specks. What are they? What am I doing wrong? I suspect they have something to do with the selenium. Is my toner too alkaline? Not alkaline enough? Thanks for your time. Dan Fuller making silent films in Wisconsin
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