Orbit Bath

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I read in an earlier post that using Orbit Bath cuts FB washing times down to 5 - 10 minutes. Anyone out there have experience with this product?

-- Christopher Hargens (ldmr@cruzio.com), December 13, 2000

Answers

The stuff works as advertised, as do other dehypo solutions.

-- Keith Nichols (knichols@iopener.net), December 13, 2000.

Look for the article Mysteries of the Vortex in _Photo Techniques_ mag several years back; also I think it was just reprinted in a PT special issue in the past couple of months.

This big article examined print washers, fixing procedures, after-fix treatment etc. I don't recall the numbers, but while the use of an HCA dramatically shortened the required wash time for given thiosulfate level, the wash time was still way longer than 5-10 minutes.

I'd speculate that 10 minutes in a high-exchange-rate washer may be sufficient for "commercial" longevity, which imho should be interpreted as "we don't care if it turns brown in five years."

For MGIVFB, Ilford specifies a five-minute first wash, 10 minutes in their wash aid, and a five-minute final wash _only if their rapid-fix method is used_. The PT article confirms that Ilford's procedure works.

Wash aids are usually sodium sulfite, sodium bisulfite, and an agent or two to prevent calcium scum etc in tap water. You can easily make your own wash aid by dissolving 20g (slightly less than a tablespoon) of sodium sulfite in a liter of water. Adding the bisulfite (5g) may be desirable for film to reduce emulsion swelling. If you don't keep the working solution sitting around (and you shouldn't) there's no need for the EDTA etc.

I'd be really careful about wash-aid manufacturers claims; in 30 years now I've never seen any data presented by TKO or Heico that shows residual thiosulfate level in what they consider to be a "sufficiently washed" print.

Think about it this way; if the claim isn't supported by reality you'll be throwing away your prints much sooner than you might otherwise.

-- John Hicks (jbh@magicnet.net), December 13, 2000.


You can spend a lot of time rinsing fixer out of prints. It's a rather asymptotic process. I'm pretty cursory about all that, and I have 40-year-old prints that look fine. On the other hand, one turns up now and then with decidedly brown edges. Do the best you can with stuff you sell, but otherwise, maybe posterity won't miss out on too much.

-- Keith Nichols (knichols@iopener.net), December 14, 2000.

Thanks for the information. I wasn't sure if Orbit Bath was a sodium sulfite solution or something different and somehow more efficient. At any rate, if I decide to try it, I'll do a residual hypo test on the results.

-- Christopher Hargens (ldmr@cruzio.com), December 14, 2000.

Realize there are two different types of processes to remove hypo.

The first is the common HCA, wash aid, or similar name. This uses sodium sulfite or something similar to reduce washing times.

The second is true hypo eliminator. This reacts with the hypo converting it to a non-harmful compound. It contains something like ammonia and hydrogen peroxide. But there are MANY problems with using this stuff. I think at least one manufacturer is selling this stuff.

-- Terry Carraway (TCarraway@compuserve.com), December 15, 2000.



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