Use of Hypo Clearing Agent?

Zonan

Zonan

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Assembling kit for developing B&W film. I see conflicting opinions of use of HCA to "shorten rinse times" vs. "not necessary, no advantage".

I will be using Ilford DD-X and HC-110, IlfoFix with both tabular and traditional grain films. Minimal water usage is important, and the claim "reduces rinsing time" would be a significant benefit if true.

Anyone with experience/knowledge on this subject?

Thanks,

Rick
 
HCA is for printing paper, not for film. Look up the Ilford method for washing film. I wash a roll of 135 film using just 750 ML of water and it takes about 10 minutes.
 
I use it with film, but it is just because I was told to use it when I was in the seventh grade. You probably don't need it for film, but like you I live in a desert area where wasting water is worse than bowing to a possible myth of Hypo.

When I was in the Army we didn't use a stop bath for film (X-ray and Photographic). But like Hypo I still do stop bath because I was taught that way.
 
I doubt it's very useful for film even if you want to conserve water. Just re-use your wash water e.g. for flushing the toilet.
Btw. hypo = sodium thiosulphate, the main ingredient in traditional (non-rapid) fixer. Not the same as hypo clearing agent or wash-aid.
 
The Hypo Clearing Agent must be washed from the film, too. It likely takes as long to do that as it does to wash the fixer from the film if you don't use HCA, so for film it has no advantage. Film is plastic, it does not absorb fixer into the base like fiber base papers do.
 
Has anyone heard or read the story about the discovery of Hypo Clearing. The story I read was that during WWII the navy discovered that on board ships where 'clean' water was at a premium they used salt water to 'wash' fixer from film and prints.

They discovered that the time was reduced to clear with salt water rinse and then a quicker fresh water rinse.

Is that true or was it internet hog wash?

By Photo Engineer (RIP) on Photrio:

HCA falls into the category of a wash aid. Wash aids come in two varieties.

One is HCA itself, which is mainly Sodium Sulfite. It is used to force the Hypo out of the coating by displacing it. You then have to displace the HAC with a wash.

The other type sometimes used is based on Hydrogen Peroxide which destroyes residual Hypo.

You can actually use non Iodized table salt. It has the same effect, and that is how this entire procedure was discovered. During the war, navy photo processors used sea water to assist in washing films and prints. The salt in sea water was acting as a wash aid.

Remember that if you use one of these, you have to dispose of this added chemical and you have to wash it out of the coating. Admittedly, the wash is less intense, but nevertheless, it is still required.
 
Thanks for clarifying this. The fewer steps, the better 🙂. My "cold water" this time of year comes out of the tap at 84 degrees F, so I need to blend chilled water to get wash water anywhere near 68-70 degrees. The less I use, the better, so that Ilford procedure will help.
 
Zonan said:
Thanks for clarifying this. The fewer steps, the better 🙂. My "cold water" this time of year comes out of the tap at 84 degrees F, so I need to blend chilled water to get wash water anywhere near 68-70 degrees. The less I use, the better, so that Ilford procedure will help.
Click to expand...

I have the same water temp problem here in Indiana during the summer. I've found that if I do my processing late at night, the water temperature is much cooler. Right now, my nighttime cold water is coming out of the tap around 72 degrees. Sometimes in the summer it can be as high as 75 in the summer at night. 72 and 75 are perfectly usable processing temps, so I just setup my developer and fixer to be the same temp as the cold tap water and use the appropriate developing time for the temp I use.

In the winter, my water is very cold, only about 50 degrees. I process in the winter at 68 and adjust the hot and cold knobs on the faucet to get 68 degree wash water.
 
charjohncarter said:
Has anyone heard or read the story about the discovery of Hypo Clearing. The story I read was that during WWII the navy discovered that on board ships where 'clean' water was at a premium they used salt water to 'wash' fixer from film and prints.

They discovered that the time was reduced to clear with salt water rinse and then a quicker fresh water rinse.

Is that true or was it internet hog wash?

By Photo Engineer (RIP) on Photrio:

HCA falls into the category of a wash aid. Wash aids come in two varieties.

One is HCA itself, which is mainly Sodium Sulfite. It is used to force the Hypo out of the coating by displacing it. You then have to displace the HAC with a wash.

The other type sometimes used is based on Hydrogen Peroxide which destroyes residual Hypo.

You can actually use non Iodized table salt. It has the same effect, and that is how this entire procedure was discovered. During the war, navy photo processors used sea water to assist in washing films and prints. The salt in sea water was acting as a wash aid.

Remember that if you use one of these, you have to dispose of this added chemical and you have to wash it out of the coating. Admittedly, the wash is less intense, but nevertheless, it is still required.
Click to expand...

Yes, true and well documented. But only for FB paper, not film, and you still need to wash out the salt. Rowland Mowrey (Photo Engineer) knew his stuff and had access to these records through Kodak.

Some important things - with modern fibre base papers there are two significant differences - seawater or HCA make less difference, and peroxide based products (so-called hypo eliminators) form bubbles under the emulsion that lift it off the base and destroy the print, so it isn’t recommended any more.

When I lived on an oceanic island in the 1990s I washed prints in seawater. It is harder to test for residual salt than thiosulfate, and the difference in rate of clearance was consistent but small. I ended up using RC paper while I was there, and doing my good prints at home.

Marty
 
No need for running water with the Ilford film washing method. I keep a 1 gallon jug of distilled water in the coolest part of the apartment in summer (about 72º on the floor in the room the AC keeps the coldest) and the warmest part of the apartment in the winter (about 68º in the utility closet with the water heater).

I use 250 ML of water for the Rodinal one-shot developer. 250 ML for the stop bath, and 3x250 = 750 ML for washing. I reuse the fixer that is stored alongside water jug. Total water used is 1250 ML.

Development starts very near the water storage temperature. All of the liquids drift slowly in the direction of the ambient air temperature but I have never measured a temperature change of the developer of more than 1.5º on the coldest or hottest days and have never bothered to adjust the development times accordingly.

I use a Kindermann 1-reel tank. The volumes would be about 1.5 times as much with a Paterson or equivalent tank. Still less than half a gallon of water.
 
You wash film to get the fixer out. If you don't get it all out then later (6 months, 6 years, ??) the negative goes bad. Having 50 years of negatives that I don't know what to do with I give my current negatives a 5 minute wash, dry, scan, and pitch.
 
I have been using the Ilford Method since before it was called the Ilford Method. A Korean War vet showed it to me in the early 60's when we both lived in a boarding house on the Lower East Side. My 60 year old negatives from those years look and scan like those I developed last week.

OTOH my son who lives in Florida and uses the Ilford Method with very hard tap water (I use distilled) and tabular grain film (I use cubic) is seeing some staining of his negatives from 10 years ago but they still scan OK.
 
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