Perma Wash

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What is the purpose of PermaWash and is it necessary?

Thanks, Derek Dixon

-- Derek Dixon (derek@pgisd.com), January 15, 1999

Answers

Perma Wash, Orbit Bath etc are "hypo clearing agents" or wash aids. They help with the removal of fixer when you wash films or prints. Although you don't really need to use a wash aid with film, given sufficient washing, what they're really good for is removing the colored sensitizing dyes that cause purple T-Max etc. You don't need a wash aid for RC prints, but otoh a wash aid is definitely needed for fiber prints. Also, the washing instructions from some wash aid manufacturers are absurd. Anyway...rather than buying the stuff, you can make a wash aid by dissolving a tablespoon of sodium sulfite in a quart of water. Immerse the fixed film in the wash aid with continuous agitation for one to two minutes, then wash it with good flow for 20 minutes. Immerse fiber paper in the wash aid for three to five minutes, then wash in an _efficient_ washer as recommended by the paper manufacturer, usually about an hour. Wash aid can be reused; the specs say about 80 prints or films per gallon but it'll develop a scum or start growing gunk probably before then. The short answer to your question is that if you want your work to be around a while you should consider a wash aid necessary. See _The Darkroom Cookbook_ by Steve Anchell, _The Film Developing Cookbook_ by Steve Anchell and Bill Troop, and Mysteries of the Vortex in past issues of _Photo Techniques_ for more info.

-- John Hicks / John's Camera Shop (jbh@magicnet.net), January 16, 1999.

Perma Wash is a washing aid that makes residual fixer easier to remove by washing. It's not absolutlely necessary, but I routinely use it before washing both film and fiber-base papers, to shorten wash time and conserve water.

-- Charles E. Albertson (chucko@siteconnect.com), January 16, 1999.

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