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Help! I am a photo teacher. It is near the end of the year and we just ran out of Hypo with no budget for buying more. Some black and white projects are still due. Is there a cheap alternative that we can make and use that is SAFE for high school students? How do I make the alternative and what are the guidelines and precautions for using it?

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    Where are you located? Maybe someone can donate a package or two... – BobT Jun 7 '18 at 1:59
  • Does it have to be hypo or will any fixer do? I pay US$ 27 for 5l of Fomafix with a capacity of 1000 films. I doubt that you will get anything cheaper. – jarnbjo Jun 7 '18 at 10:55
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The fix solution you seek is one of the most inexpensive chemicals of the black and white process. You can use most any fixer formulas. In other words, fixer for X-ray, fixer for film and paper. You might buy some from a local camera shop or photo studio. In any event, the stuff is benign. You be at ease, allowing your students to work with it. It has the smell of vinegar because most formulas contain acetic acid (concentrated vinegar). Call or go to your local hospital, they likely will give you a package of X-ray fixer after you plead your case. You can test - swish a snipping of 35mm tongue in paper cup filled with fixer. Do this in the light. You will see the film change from opaque to transparent. Time this reaction. Fix time for film and paper is double the time it takes for the film to clear. If the film does not clear when performing this test, the solution is contaminated of exhausted.

Hospital and dental have mainly phased out chemical based X-ray for digital however, some chemical X-ray is likely in use. Just as likely, the local hospital will have some boxes of fixer in the basement. Make some calls.

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    I misread your question. You want a hypo clearing agent not hypo. You don't need to use a hypo clearing agent. Wash film in running water for 15 to 30 minutes. Wash papers for 30 minutes single weight and 60 minutes double weight. This will work just as well. If you think you must use a hypo clearing agent, table salt will also work. Make a 3% solution (about the same as sea water). Swish the photo material in the salt solution, then remove and wash in fresh water for 5 minutes. Hypo clearing agents are just simple salt solutions just that they use different salts. Table salt works. – Alan Marcus Jun 7 '18 at 15:28
  • Get the scoop on salt water --Kodak publication "Photographic Chemistry" by George T. Eaton Kodak Research Lab Rochester page 108 "reduces film washing time to about 1/3 reduces print washing time 1/5 to 1/10 of normal. – Alan Marcus Jun 7 '18 at 21:55
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    The original question said "Hypo". Someone else edited in the "clearing agent" part, probably mistakenly. – Michael C Jun 8 '18 at 1:58
  • @ Michael Clark -- Thanks for the clarification - Hopefully Derek can find some fixer for cheep or free. As you known plain sodium thiosulfate will work. The idea to use table salt as clearing agent stems from world war II ship board photo lab -- it works. – Alan Marcus Jun 8 '18 at 5:10
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Can't say that I've personally tried this one, but my copy of The Darkroom Cookbook reports the following:

Acid Hypo:

  • Water at 125F/52C, 2.0 liters
  • Sodium thiosulfate, 480.0g
  • Sodium bisulfate, 45.0g

Use undiluted. Unlike Plain Hypo this fixer can be saved and reused. It allows easy toning with direct toners, such as selenium.

The plain hypo formula is a bit more simplistic, and I can type if here if you want, but it seems a poor fit for student use because it "has poor keeping qualities." In other words, it's a mix and use, fast, kind of solution.

Here's the CDC guide on Sodium Thiosulfate.

And here's the CDC guide for sodium bisulfate.

As with all chemical mixing processes, it's probably best that you do the mixing, and let your students use the solution with the same cautions they'd normally use with hypo.

Photographer's Formulary has the Bisulfate at 1 lb. for $7.95 (~453g) and the Thiosulfate at $49.95 per 10 lbs. (~4535g).

That would give you ~10 batches of 2 liters each for ~$56 (so, let's say a total volume of 20 liters, or $2.80 / liter)

BH has Ilford's Rapid Fixer at $34.95 / 5 liters and recommends using either a 1+4 or 1+9 dilution. After diluting, the cost per liter is either ~$1.40 (1+4) or ~$0.70 (1+9).

So, making it yourself really only becomes an alternative to buying if you can source the ingredients for significantly cheaper than buying from Photographer's Formulary. Maybe the chemistry department can help you out there?

  • Buying raw chemicals to make simple photographic agents from scratch is usually more expensive, sometimes even much more expensive, than to buy the chemicals ready-made. – jarnbjo Jun 7 '18 at 11:10
  • @jarnbjo did some math and, indeed, Photog's Formulary is, at best, twice as expensive and, at worst, four times. – Hueco Dec 10 '18 at 18:07
  • Buying raw chemicals in smaller amounts is usually quite expensive everywhere. If I go wholesale, I can easily find sodium thiosulfate for US$0.45/lb and sodium bisulfate for US$0.33/lb here in Germany, but we are then talking about orders of a ton or more. If you require such amounts, you can probably get a much better deal on the ready-to-use fixer as well, but I buy my fixer (Foma) in 5l canisters for about US$20 (ex tax) here. – jarnbjo Dec 11 '18 at 20:42
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Plain fixer formula:

750 ml Water
240.0 g Sodium Thiosulfite
1000 ml Water-to-make

Fixing time is around 5 to 10 minutes

  • It would very helpful if you would explain the details in how to mix this properly/safely. Mixing chemicals is not something someone should do unless they understand the chemicals and the proper way ( order to add them together ) and the consequences of doing it incorrectly. While adding water to chemical might be safe adding the same chemical to water may cause an explosion. Plus detailed answers are the goal on stack exchange. – Alaska Man Dec 11 '18 at 22:00

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