Has anyone ever used this bleach?

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I was reading in Tim Rudman's "Master Printing Course" and he gives a formula and description of a bleach that supposedly Ralph Stiener used to preserve the detail in his cloud formations. (the formula consists of potassium ferricyanide, hypo and a small amount of sodium hydroxide. This is exactly what I wish to do as I find that my photographs which include vast amounts of sky lack the "sparkle" that I wish they would have. I have taken all the neccessary steps to insure that I am not fogging the paper from light leaks and safelight illumunation. I develop negatives which include lots of sky and clouds in pyro as I wish to have the utmost separation in the high values and I don't want to lose that in a standard ferri bleach. Has anyone used this bleach and what were your experiences with it? Any info. or recommendations is appreciated.

-- Brian Jefferis (jefferis@erols.com), April 15, 1999

Answers

Brian -

If what you want to do is just brighten the highlights slightly (sort of take the "fog" out of them) let me suggest a very controllable, easily made reducer. A very mild reducer can be made as follows:

Use Kodafix fixer. Mix the fixer into 1 gallon of water. Use 1 part fixer to 4 parts water and add 15 grams of citric acid per 1000 ml of solution.

I like to wash my prints prior to this treatment as the effect is slower and more predictable. Residual fixer in the print will speed up the process and as the paper fixer gets older and more loaded with silver, you can get some uneven reduction in the print.

When the reducer turns milky white, you need to mix fresh reducer. I like to mix 1000ml of fixer and water and use it about 200ml at a time in the tray. I add the citric acid into the tray and dissolve it just prior to putting the print. It will dissolve in less than 20 seconds. Putting the citric acid in at the very last moment "activates" the reducer and keeps the reducer action as high as possible without deteriation of the solution because it has been sitting while you work on prints.

I have a set of measuring spoons and have found that slightly short 1/4 teaspoon of citric acid in the 200 ml of solution is about right. I would suggest that you weigh out some citric acid using a measuring spoon so that you can get the visual equivalent. I have found that the measuring spoon method gets me repeatedly with .5 gram of the correct amount. Since the bleach is so mild, a little under or over doesn't really seem to matter.

I also find that if I squeegee both side of the print to get any water droplets off the print it helps as the amount of working solution is minimal and the water will prevent the reducer from working for a short period of time on the area where the drop is sitting giving the possibility of uneven reduction if the drop is on top of a white area.

Do not user fixer that you have used for fixing prints or film as it has silver in it. I keep a separate 1 gallon jug of Kodafix on-hand specifically for clearing whites in my prints with the citric acid.

Mix the reducer fresh each time you want to use it. It will give off sulfur dioxide as a by-product when the citric acid is first put into the diluted fixer. So use it in a well ventilated area. I like the 1:4 dilution as the action is slow & I can monitor it. The longest I have ever left a print in this solution is about 2 minutes. If you want faster action change the dilution to 1:2, and of course, slower dilute it more.

This reducer will also clear any dicroic fog from the print as well.

When you are satisfied with the results, you need to give it a full wash, treatment with hypo eliminator etc.

You can also use Kodak Rapid fixer in the same way, but I find the production of sulfur dioxide is somewhat greater with the Rapid Fixer than with the Kodafix.

The bleach will not touch the greys or blacks as it is so mild and is used up so rapidly. If you mix it stronger, you will see some effect on the light greys if you leave it in too long.

-- steve (swines@egginc.com), May 03, 1999.


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