What does the Army know that I don't know?

[Paul Howell]

In another thread someone posted a number of U.S Navy and Army correspondence courses. As I fipped thourhg them I found an Army Course on shooting in climate extremes printed in 1987. Here is an odd direction.

c. The use of hypo eliminators is almost mandatory in the arctic. This requires very little water to wash film and prints. Use the following recipe to prepare hypo eliminator if you cannot obtain it through supply channels. HYPO ELIMINATOR Water 16 oz (500 ml) Hydrogen Peroxide (3%) 4 oz (125 ml) Ammonia solution (3%) 3 1/4 oz (100 ml) Add water to make 32 oz (1 liter)

And by hypo eliminator they mean hypo eliminator, not hypo clearing.

 

[wiltw]

Due to low availability of fresh water, lots of rinsing is not readily possible, therefor use of hypo clearing agent becomes a necessilty. Hypo clearing agent = hypo eliminator

 

[Paul Howell]

Hypo eliminator is not a clearing agent, it was used after a standard long wash to eliminate any residual hypo, then washed again. Kodak stopped recommending hypo eliminator in the early 60s as a trace of hypo is needed for archival storage. Because of a second wash it uses additional water, not less.

 

[gorbas]

Hypo clearing agent = hypo eliminator
It's not the same thing. Probably PE can give you full scope of the issue?
One of the issue that extremely low level of hypo is beneficial to preserving photographic print. I'm not talking here about not washing your films or prints.

 

[Arklatexian]

In another thread someone posted a number of U.S Navy and Army correspondence courses. As I fipped thourhg them I found an Army Course on shooting in climate extremes printed in 1987. Here is an odd direction.

c. The use of hypo eliminators is almost mandatory in the arctic. This requires very little water to wash film and prints. Use the following recipe to prepare hypo eliminator if you cannot obtain it through supply channels. HYPO ELIMINATOR Water 16 oz (500 ml) Hydrogen Peroxide (3%) 4 oz (125 ml) Ammonia solution (3%) 3 1/4 oz (100 ml) Add water to make 32 oz (1 liter)

And by hypo eliminator they mean hypo eliminator, not hypo clearing.

I might be wrong but, to non-chemists doing B&W processing, hypo eliminator means what is now known as "Hypo Clearing Agent" and was meant to be used as such. To take "hypo eliminator" literally would mean to use something that took the place of acid fixer, not neutralize it in already fixed film or prints. The people that I knew who had been photographers in the South Pacific during WW2, had a similar need and learned to wash prints (I don't remember if they also said films) in seawater with a final freshwater rinse. It worked so well ridding the prints of fixer that "after the war", HCL was introduced. Water, especially seawater which might still be liquid at below 32 F/0 C, probably is not efficient as a wash water, hence the instructions on how to make your own HCL.......Regards!

 

[Arklatexian]

Hypo clearing agent = hypo eliminator
It's not the same thing. Probably PE can give you full scope of the issue?
One of the issue that extremely low level of hypo is beneficial to preserving photographic print. I'm not talking here about not washing your films or prints.

+1

 

[mshchem]

Hypo eliminator is not a clearing agent, it was used after a standard long wash to eliminate any residual hypo, then washed again. Kodak stopped recommending hypo eliminator in the early 60s as a trace of hypo is needed for archival storage. Because of a second wash it uses additional water, not less.

You are correct sir. The use of hydrogen peroxide for "nuking" thiosulfate is not a good idea. I will defer to PE and others for the exact explanation. Kodak warns people about this.
I use Kodak HCA for fiber prints and film (gets the purple out). The confusion comes from Kodak published a formula for "Hypo Eliminator HE-1" this is the ammonia water, hydrogen peroxide concoction that could cause problems.
I'm sure that if it meant hauling water, the Army folks got pretty creative. .
Obviously there's all sorts of wash aids out there.

 

[ic-racer]

I have never heard of hypo eliminator being called "Hypo Clearing Agent." Is this misunderstanding something new?

 

[removed account4]

I might be wrong but, to non-chemists doing B&W processing, hypo eliminator means what is now known as "Hypo Clearing Agent" [...]

they were 2 different chemistries and used for different reasons. i've never used hypo eliminator, and always heard never to use it, but to use clearing agent instead. maybe for some they were interchangeable but for others they are completely different beasts.

 

[Paul Howell]

Hypo eliminator is not hypo clearing, the formula quoted is for hypo eliminator.

As I've thought about it, I think the Army had a very good idea. In very cold weather in the field and very cold water, say wash water temp is in the 40,. 50 or low 60s the only way to get most of the hypo out is with hypo eliminator, even after using hypo clearing, so hypo clearing agent, long wash then the hypo eliminator to help compensate for the cold wash water. At those temps even using hypo eliminator may not get all the hypo out of fiber based paper. And it was recommended to use hypo eliminator for film as well, never seen anyone recommend hypo eliminator for film.

On the other hand even thought the course if from the 80s may the text may date back to the 40s or 50s when hypo eliminator was in common use.

 

[mshchem]

I have never heard of hypo eliminator being called "Hypo Clearing Agent." Is this misunderstanding something new?

 

[mshchem]

Hypo eliminator is not hypo clearing, the formula quoted is for hypo eliminator.

As I've thought about it, I think the Army had a very good idea. In very cold weather in the field and very cold water, say wash water temp is in the 40,. 50 or low 60s the only way to get most of the hypo out is with hypo eliminator, even after using hypo clearing, so hypo clearing agent, long wash then the hypo eliminator to help compensate for the cold wash water. At those temps even using hypo eliminator may not get all the hypo out of fiber based paper. And it was recommended to use hypo eliminator for film as well, never seen anyone recommend hypo eliminator for film.

On the other hand even thought the course if from the 80s may the text may date back to the 40s or 50s when hypo eliminator was in common use.

Good points, I'm not sure when Kodak started selling HCA, I have a 1951 Kodak book on all their ready made stuff, theres no mention of Kodak Hypo Clearing Agent. I remember in the 60's Kodak Dataguide Kodak stressing the need for HCA to wash in cold water. If you were some place without realitively warm water you would never get hypo out.

 

[Photo Engineer]

Peroxide Hypo Eliminator formulas destroy the Thiosulfate ion by oxidaton. Hypo clearing or wash aids act to displace hypo from the coating and leave it clear of Thiosulfate.

One must be careful thought that in destroying hypo, one does not release the complexed Silver back into the coating. Bad.

PE

 

[Trey]

View attachment 231479

They’re two different things.

 

[mshchem]

They’re two different things.

Absolutely agree.

 

[RauschenOderKorn]

Peroxide Hypo Eliminator formulas destroy the Thiosulfate ion by oxidaton. Hypo clearing or wash aids act to displace hypo from the coating and leave it clear of Thiosulfate.

One must be careful thought that in destroying hypo, one does not release the complexed Silver back into the coating. Bad.

PE

Doesn´t peroxide also soften the emulsion, possibly to the extent that it can come off the base?
I think there was a formula in Haist´s book to do that (can´t remember exactly what it was, though).

 

[Paul Howell]

John Carroll's 1975 edition of Photographic Facts and Formulas recommends using a 1 percent solution of formaldehyde to harden fiber base paper to prevent sticking on belt dryers, and either a 1 percent solution of potassium bromide for any change in tone, or 1 percent solution of sodium sulfite if the whites have a yellow cast. I guess film or RC paper can be hardened with potassium bromide as well.

The Army's course is the first time I have ever seen a recommendation for using hypo eliminator with film, use of hypo eliminator was out of fashion by the time RC paper was in common use. In the mid 60s our college used hypo eliminator, then either a Kodak or GAF tech told our lab guy that hypo eliminator was counter productive as a small residual of hypo was needed for archival storage. I also recall that Ansel Adams recommend against using hypo eliminator but he did use hypo clearing. When an Air Force Photographer I don't recall ever discussing using hypo eliminator.

 

[Photo Engineer]

Ammonia induced softening is probably of little concern in the face of the alternative. Also, modern emulsions are much better hardened. Bromide hardens nothing.

PE

 

[Paul Howell]

My mistake, I should have said formaldehyde could be used to harden film and RC paper.

 

[cmacd123]

the navy formual is close to this one from "archive Org"
Hypo Eliminator and Test Solutions

KODAK FORMULA HE-I

Hypo eliminator

Metric Avoirdupois

500 c.c. . . . Water 40 oz.

125 c.c. . . . Hydrogen peroxide

(3% solution*) . . . . 10 oz.

100 c.c. . . . Ammonia (3% solutionf) . . 8 oz.

1000 c.c. . . . Water to make 80 oz.

* i.e., 10 vol. solution, as purchased.

| To make 3% ammonia, dilute 9 parts of .880 ammonia to make 100 parts
of solution.

Hypo eliminators are not usually required in processing negative materials.
In the case of prints, however, traces of hypo are tenaciously held by the
paper fibres and may lead to fading of the image on long keeping under
adverse conditions. HE-I used as directed converts the hypo to inert
sulphate and also facilitates its removal.

DIRECTIONS FOR USE

Wash the prints for about 30 minutes at 65° to 70° F.* in running water
which flows rapidly enough to replace the water in the vessel (dish or tank)
completely once every five minutes. Then immerse each print for about
six minutes at 70° F. in the hypo eliminator solution ('Kodak' HE-I) and
finally wash tor about 10 minutes before drying.