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h2oman
27-Mar-2009, 10:42
Within the next 24-48 hours I will probably be doing my very first film developing. I bought some of my chemicals, some were given to me. One thing that was given was something called "Universal Hypo-Wash." There are no directions for what it is used for, but I'm gathering this is something I wash with after fixing and before washing with water, and it somehow aids in the washing?

For mixing my developer and fixer I was thinking of using paint stirring sticks. Is this a bad idea for some reason? I figure I can designate a permanent stick for each.

venchka
27-Mar-2009, 11:07
Save it for getting rid of fixer in fiber prints. Skip it for film.

Kevin Crisp
27-Mar-2009, 11:11
I am not familiar with that particular product but it is a washing aid that cuts down washing time, especially for fiber based prints. It can cut hours off the washing time. I wouldn't use it without instructions. It is probably similar to Permawash, which is what I have always used. It can help clear the pink cast on T Grain films, but since film washes so easily I rarely use a washing aid with film.

Usually the washing aid is used after fixing and a brief water rinse.

Painting sticks are wood and will absorb chemicals and stain. They might leave wood fibers in the chemicals. Just go buy one all plastic cooking spoon (preferably one with some slots in it for draining) and mix chemicals with that. You will only need one because it rinsing off easily.

CG
27-Mar-2009, 11:31
venchka is right. Film and RC printing papers are easy to wash and for them, washing aids are something of overkill.

Use hypo clearing agents such as yours when printing on fiber based printing papers. Fiber based papers "cling" rather tenaciously to the fixer ("hypo") and thus benefit from "hypo clearing" agents as an aid to complete washing.

The fix is necessary, but must be removed thoroughly for photo materials to be permanent.

It's sort of a daisy chain: before all else, you need the built in silver halides to create a light sensitive surface; the final image will actually be metallic silver, but when that's done, all the unused silver must be removed, so you use fixer, also known as "hypo" - sodium thiosulfate or similar - to extract the unused silver compounds.

But, the fix, while necessary must then in it's turn be removed, thus the need for washing.

And for fiber based printing papers, hypo clearing agents do the job of getting hypo out of the paper better and faster. For archival printing on fiber based paper, hypo clearing agent is one of the necessities.

Ken Lee
27-Mar-2009, 11:31
Dunno about Perma Wash, but the sole active ingredient in the standard formula (http://www.digitaltruth.com/data/washaid.php) for "washing aid" is Sodium Sulfite.

You can purchase (http://www.artcraftchemicals.com/)it as a powder in bulk for next-to-nothing, and make a working solution by adding 1 teaspoon into a liter of water. You can toss it out when done.

(The other ingredient, Sodium Metabisulfite, is a stablizer, and is only required if you plan to store it on the shelf).