Hypo clear formula

Any errors or omissions you come across in the Darkroom Cookbook.
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markbau
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Hypo clear formula

Post by markbau »

In the article Mysteries of the Vortex published in DCCT many years ago, the authors said that a heaped teaspoon of Sodium Sulphite in one litre of water was an effective wash aid. First, a question, does anyone know for sure that this is, in fact, a substitute for a wash aid such as Ilford Wash Aid or Kodak Hypo clear? Should this formula be in the next edition of the Cookbook?
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sanchell
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Re: Hypo clear formula

Post by sanchell »

Hypo Clearing Agent (HCA) is nothing more than sodium sulfite. The formula in the DCB is

Water at 125F/52C, 750.0 mol
Sodium sulfite, 200.0 g
*Sodium bisulfite, 50.0 g
Water to make 1.0 liter

*The sodium bisulfite lowers the pH in order to prevent softening of the film emulsion. If paper is to be used the bisulfite may be left out in order to improve the paper's gloss.

In other words, 200 ml of sulfite in 1 liter of water if you don't have any bisulfite handy. OR ... dump a heaping teaspoon of sulfite in 1 liter of water.

Now, markbau, buy the darn book!
Do it in the Dark,



Steve Anchell
markbau
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Re: Hypo clear formula

Post by markbau »

I have 2 editions of the Darkroom Cookbook! (Actually, I've bought the 4th edition twice, gave my first copy to a friend) I found the formula in the 4th edition after I posted.
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sanchell
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Re: Hypo clear formula

Post by sanchell »

They make great stocking stuffers!
Do it in the Dark,



Steve Anchell
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