Something odd occurred in my half-gallon of working-strength (about 1+9) Rapid Selenium Toner and before I mix up more I hope to find out what happened. This was mixed using steam-distilled water - I have a counter-top distiller and make my own.
The solution was fine 4 days ago when I last used it. As per usual, I had added a bit of "fresh" (purchased in May 2005, but this bottle is now nearly used up) stock from the Kodak bottle before starting my session, and at the end I coffee-filtered the solution back into its clear half-gallon glass bottle. My liquid chems are stored in the basement at a pretty constant ~68F. It's dark in that room except when I turn on the incandescent ceiling light to fetch things.
Yesterday, 3 days after the last use, I noticed a thin translucent white coating on the bottom and lower sides, about 1/4 way up from the bottom, of the bottle. Today I dumped the contents and washed it out. The white film wouldn't come off with hot water and shaking, but I could easily remove it using a small piece of paper towel pushed into the bottle and moved around with a dowel.
This bottle has been stored in the same location and used several times in the past few weeks, and has been used for diluted (always with distilled water) KRST exclusively since I purchased it (the glass bottle) new. I've filtered out the usual black flecks at each use, but have had no other issues until this time.
When toning I start with previously well-washed dry prints, rewet for a few minutes in tap water, drain and place into the toner, drain and place into 2% sodium sulfite for a 5-10 minutes, then into the washer. I'm careful to avoid back-contamination. My tap water has very low mineral content. I've never had issues with print staining so I believe my processing regimen (two baths of Ryuji Suzuki's neutral fix, 2% sodium sulfite for 5-10min, wash for ~30 min) is good.
Does anyone have any idea what might have happened? I have unopened bottles of stock from 2008 and 2009, along with newer ones, and hope to use it all. I'm not aware that KRST stock has a shelf life, but that could be lack of knowledge on my part. But remember that this stuff worked just fine over the past few weeks and suddenly went weird...
The solution was fine 4 days ago when I last used it. As per usual, I had added a bit of "fresh" (purchased in May 2005, but this bottle is now nearly used up) stock from the Kodak bottle before starting my session, and at the end I coffee-filtered the solution back into its clear half-gallon glass bottle. My liquid chems are stored in the basement at a pretty constant ~68F. It's dark in that room except when I turn on the incandescent ceiling light to fetch things.
Yesterday, 3 days after the last use, I noticed a thin translucent white coating on the bottom and lower sides, about 1/4 way up from the bottom, of the bottle. Today I dumped the contents and washed it out. The white film wouldn't come off with hot water and shaking, but I could easily remove it using a small piece of paper towel pushed into the bottle and moved around with a dowel.
This bottle has been stored in the same location and used several times in the past few weeks, and has been used for diluted (always with distilled water) KRST exclusively since I purchased it (the glass bottle) new. I've filtered out the usual black flecks at each use, but have had no other issues until this time.
When toning I start with previously well-washed dry prints, rewet for a few minutes in tap water, drain and place into the toner, drain and place into 2% sodium sulfite for a 5-10 minutes, then into the washer. I'm careful to avoid back-contamination. My tap water has very low mineral content. I've never had issues with print staining so I believe my processing regimen (two baths of Ryuji Suzuki's neutral fix, 2% sodium sulfite for 5-10min, wash for ~30 min) is good.
Does anyone have any idea what might have happened? I have unopened bottles of stock from 2008 and 2009, along with newer ones, and hope to use it all. I'm not aware that KRST stock has a shelf life, but that could be lack of knowledge on my part. But remember that this stuff worked just fine over the past few weeks and suddenly went weird...
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