Prints turning brownish/orange, washed out - bad fixer?
Help, I am using Michael and Paulas fixer formulas and never had a problem until recently with new sodium thiosulfate prismatic rice crystals from Photographers Formulary...could they be bad? (and I have used this formula with success on tons of prints before, no problems).
When I add the sodium bisulfite to the sodium thiosulfate it turns milky/cloudy, which I don't remember happening previously....or is my sodium bisulfite bad?
I wasn't sure exactly what was happening so I left some prints in the second fixer (per M & P only sodium thiosulfate) and sure enough they went light/brownish orange).
Do I have bad fixer?
It is mixed FRESH right before I print too.
I also used rotated fresh trays for fear that maybe something got contaminated....well the same thing happened...
I finally got so ticked, I used t4 fixer, normally used for just film and it seems to work fine....so, bad chems?
Brownish orange stains are usually an indication of contamination. Are you using tongs or gloves? Are the trays clean?
I don't really remember ever having a contamination problem like this with a 2 bath fixer that I alone was using. I have had contamination problems with in cases where I was working in the University Darkroom and sharing chemicals.
Plain hypo prisms (Sodium Thiosulfate pentahdryate) will dissolve in water and make a clear solution with no cloudiness. Adding about 100 - 200 grams in 500 ml of water will cause the water to become cold, so starting with warm water (about 100 F) helps. Then dilute to 1 liter. This makes a good fixer if the solution is clear and it is used as-is fresh.
If you try this method on a few prints and it works, then the hypo is good.
If you add sodium bisulfite to it, and it becomes cloudy then the bisulfite is likely bad. If the fixer at this point smells sour and strong or like rotten eggs, then the fixer has been ruined by whatever you have just added.
PE thanks! Yup, turns milky and smells REALLY STRONG, like overpowers the darkroom....and in a short while turns to a bad smell like rotten eggs, but not immediately.......sounds like my bisulfate is bad.....
I had no idea that sodium bisulfate could go bad...How long does it last in powder chemical form?
Uh oh...I think I realized what I was doing wrong.....I was using sodium bisulfate instead of sodium bisulfite! Crud, there is a difference huh? Perhaps that is the reason.....
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Yeppers. Bisulfate is ungood in the fixer. Use Sodium Bisulfite.
However, bisulfites can turn into bisulfates by aerial oxidation. So.....
Read the label, read the formula, read them both again to make sure, then make sure you use fresh chemicals.
Bisulfate is very acidic; can be used in place of sulfuric
Originally Posted by Scott Peters
acid in some formulas. It with thiosulfate will produce
sulfur dioxide and a precipitate of sulfur. Dan