RE: VDB nasty staining problem
Oops! Sorry, "sodiumthiosulfate toner" in the last paragraph had to be "sodiumthiosulfate fixer". It was a typo... I was not including salt in the toner + IIRC, my wash protocol between toner and fixer was "at least 5 minutes + at least 10 water changes". (No running water)... Why do you tone that long - is it because of large surface / small toner amnt.? (I was reusing 1lt toner for 8.5x11" prints and toning was pretty fast.) Regards, Loris. -----Original Message----- From: david drake [mailto:daviddrakephoto@sympatico.ca] Sent: Wednesday, May 02, 2007 3:26 PM To: alt-photo-process-l@usask.ca Subject: Re: VDB nasty staining problem Loris, thanks for your comments. I haven't received anything from anyone else. I have been using the toner one shot (as Sandy King recommends). I'm making large prints (14x20") which require aprox. 140 ml per print of toner. I do also use plain sodium thiosulphate as fixer. I'm assuming that when you say sodium thiosulphate 'toner' you meant that you didn't use toner? The gold/thiourea toner I'm using includes some sodium chloride (5 gm/250 ml toner) which perhaps works to balance out the acidity? But you have a very good point. I will try washing for longer between toner and fixer. This is the toner formula that I am using: Gold chloride (1% solution)- 12 ml Thiourea (1% solution)- 12 ml Tartaric acid (10% solution) - 12 ml Sodium chloride - 5 gm Distilled water to make 250 ml. I am also going to try different paper today and other combinations to try and narrow down this rather upsetting development. thanks Loris, david On 2-May-07, at 5:18 AM, Loris Medici wrote: David, I don't know if you got offline replies to this but will comment anyway: Could it be that your toner is exhausted (and therefore acting in a funny manner)? 8 minutes sound very long to me; it was usually taking not more than 2-4 minutes (30 seconds with very fresh toner) to tone my prints with gold/thiourea toner... When have you mixed it and how many prints did you process with it? (This question applies only in the case you're not using fresh toner for every print.) One more speculation: I was using plain sodium thiosulfate toner with my Vandykes (2% for 2 minutes - refreshing it every 3 prints). AFAIK gold/thiourea toner is acidic, maybe the wash after toner is not long enough to clear it completely so that it won't react (somehow!?) with the alkaline fixer. Have you tried plain fixer? Regards, Loris.
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