</span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (Darkroom ChromaCrafts @ May 6 2003, 06:09 PM)</td></tr><tr><td id='QUOTE'> </span><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (OleTj @ May 2 2003, 02:49 AM)</td></tr><tr><td id='QUOTE'> Leafing through a book from 1904, I came across the following interesting hint:
"The addition of Sodium bisulfite to the fixer (plain hypo) is highly recommended. Not only will it increase the life of the fix, but it will also remove the unsightly brownish stain that sometimes occurs when using certain developers (notably pyrogallol)".
Translation and rewording from German is entirely mine.
Now my question is: Is this the reason nearly all commercial fixers are acidic? To REMOVE the Pyro stain??? Or does someone know differently?
I fear this could be another of those weird traditions from the days of glass plates - like the standard sizes for printing papers... </td></tr></table><span class='postcolor'>
Well, I wonder if that is why I have five bottles of the stuff around the shop. I got only about 15 days of actual training and I keep coming across chemicals I have no idea what to do with. I just found out how to use potassium ferrocyanide about a month ago. I got about a pound and a half of it.
What proportions did the book suggest. . . </td></tr></table><span class='postcolor'>
If you're using commerically prepared fixer I doubt you need to worry. I think you're asking about the sodium bisulfite? Most commerical chemicals aren't likely to be improved by adding things.
For the unknown chemicals you could try Jack's chemical website:
Also you might want to look at:
The Darkroom Cookbook by Anchell and Troop.
But unless you're mixing your own chemicals up I don't know if you really need to.