Question regarding poor print wash

Doremus Scudder · Apr 20, 2021

Richard,

I guess I'm giving up trying to reason with you at this point. Your own posts demonstrate that you are confused about this. Although I haven't received my copy of "Creative Elements" yet, the excepts you posted lead me to believe that it and the literature from Kodak (and many other sources about this) do not contradict each other. I believe the misunderstanding lies with you. You seem to not be able or willing to see the difference between tests for adequate fixing (i.e., tests for residual silver) and tests for adequate washing (i.e, tests for residual hypo/thiosulfate compound). Nevertheless, they are two different things.

So for those who are following this thread and those who will read it in the future, I'd like to prevent misinformation from spreading and emphatically make the distinction:

There are separate tests for adequate fixing and adequate washing. Note that an inadequately-fixed print can be washed well and pass the washing test.

The Kodak HT-2 test is a test for residual hypo, i.e. a test for remaining thiosulfate compounds from the fixer that haven't washed out.
It is a test for adequate washing.
It uses silver nitrate as the test reagent. It leaves a stain on the tested area proportional to the amount of residual fixer compounds left in the paper/film being tested. Originally, it was sold together with a "Hypo Estimator," which was a comparison scale. Nowadays, you can find it for download on the Internet from various sites.

It is worth noting that there is an older Kodak test for washing, the HT-1a test, which uses potassium permanganate as a reagent. Kodak gives it in a 1944 book of formulas, but only mentions the HT-2 test in later publications. Steve Anchell's Darkroom Cookbook, 3rd. ed. gives this formula, but not HT-2. This is also likely the same test R.Gould mentions in his posts above from his 1935 source.

The Kodak ST-1 test and the sodium-sulfide test that Ilford describes in their literature are identical, and is a test for residual silver.
It is a test for adequate fixing.
It uses sodium sulfide as a test reagent. It, too leaves a stain on the tested area, but this time in proportion to the amount of residual silver compounds in the print/film that have not been adequately fixed. Any stain other than a very faint cream-colored stain indicates improper fixation. Note that this test needs to be done on a well-washed print, but that washing is not what is being tested.

The test using Kodak Rapid Selenium Toner is an alternative test for residual silver and can be used in place of ST-1. It uses selenium as a test reagent.
It, too, is a test for adequate fixing.
And, it too leaves a stain on the tested area proportional to the amount of residual, inadequately-fixed, silver compounds in the print/film tested. Many (myself included) prefer this test to the ST-1 test since the test solution lasts much longer and it doesn't stain things as readily as silver nitrate.

Formulas and instructions for use for the above are available in the Kodak document I linked to above and from numerous other sources on the Internet and in print. Anchell's Darkroom Cookbook, 3rd ed. gives both the ST-1 and selenium toner tests for residual silver.

Best,

Doremus

grain elevator · Apr 21, 2021

Doremus, thank you for the definitive summary. In the section about selenium toner you write "it doesn't stain things as readily as silver nitrate" - that's somewhat confusing as it isn't an alternative to silver nitrate (HT-2), but to sulfide (ST-1).

R.Gould · Apr 21, 2021

Doremus Scudder said:
Richard,

I guess I'm giving up trying to reason with you at this point. Your own posts demonstrate that you are confused about this. Although I haven't received my copy of "Creative Elements" yet, the excepts you posted lead me to believe that it and the literature from Kodak (and many other sources about this) do not contradict each other. I believe the misunderstanding lies with you. You seem to not be able or willing to see the difference between tests for adequate fixing (i.e., tests for residual silver) and tests for adequate washing (i.e, tests for residual hypo/thiosulfate compound). Nevertheless, they are two different things.

So for those who are following this thread and those who will read it in the future, I'd like to prevent misinformation from spreading and emphatically make the distinction:

There are separate tests for adequate fixing and adequate washing. Note that an inadequately-fixed print can be washed well and pass the washing test.

The Kodak HT-2 test is a test for residual hypo, i.e. a test for remaining thiosulfate compounds from the fixer that haven't washed out.
It is a test for adequate washing.
It uses silver nitrate as the test reagent. It leaves a stain on the tested area proportional to the amount of residual fixer compounds left in the paper/film being tested. Originally, it was sold together with a "Hypo Estimator," which was a comparison scale. Nowadays, you can find it for download on the Internet from various sites.

It is worth noting that there is an older Kodak test for washing, the HT-1a test, which uses potassium permanganate as a reagent. Kodak gives it in a 1944 book of formulas, but only mentions the HT-2 test in later publications. Steve Anchell's Darkroom Cookbook, 3rd. ed. gives this formula, but not HT-2. This is also likely the same test R.Gould mentions in his posts above from his 1935 source.

The Kodak ST-1 test and the sodium-sulfide test that Ilford describes in their literature are identical, and is a test for residual silver.
It is a test for adequate fixing.
It uses sodium sulfide as a test reagent. It, too leaves a stain on the tested area, but this time in proportion to the amount of residual silver compounds in the print/film that have not been adequately fixed. Any stain other than a very faint cream-colored stain indicates improper fixation. Note that this test needs to be done on a well-washed print, but that washing is not what is being tested.

The test using Kodak Rapid Selenium Toner is an alternative test for residual silver and can be used in place of ST-1. It uses selenium as a test reagent.
It, too, is a test for adequate fixing.
And, it too leaves a stain on the tested area proportional to the amount of residual, inadequately-fixed, silver compounds in the print/film tested. Many (myself included) prefer this test to the ST-1 test since the test solution lasts much longer and it doesn't stain things as readily as silver nitrate.

Formulas and instructions for use for the above are available in the Kodak document I linked to above and from numerous other sources on the Internet and in print. Anchell's Darkroom Cookbook, 3rd ed. gives both the ST-1 and selenium toner tests for residual silver.

Best,

Doremus

As you can see from my quotes from Creative elements these tests are described with in the book as FILM AND PAPER RESIDUAL FIXER TEST KODAK HT2 and the second is alsostated as FILM AND PAPER RESIDUAL FIXER TEST.so you are telling me both of the books I quote from are incorrect, two books, one volder gthen me, oth giving the same formulas for film and paper residual fixer tests are incorrect, I am NOT confused, I would say YOU are confused, I quoted directly from 2 books, giving 2 formulas for residual fixer tests, and you say they are b both wrong and you are correct, you believe what you want, but a heck of a lot of photographers this side of the pond are all incorrect,

grain elevator · Apr 21, 2021

R.Gould said:
As you can see from my quotes from Creative elements these tests are described with in the book as FILM AND PAPER RESIDUAL FIXER TEST KODAK HT2 and the second is alsostated as FILM AND PAPER RESIDUAL FIXER TEST.so you are telling me both of the books I quote from are incorrect, two books, one volder gthen me, oth giving the same formulas for film and paper residual fixer tests are incorrect, I am NOT confused, I would say YOU are confused, I quoted directly from 2 books, giving 2 formulas for residual fixer tests, and you say they are b both wrong and you are correct, you believe what you want, but a heck of a lot of photographers this side of the pond are all incorrect,

There is no disagreement about HT-2, we all agree it's a residual fixer test, so we could drop that. Contentious is the use of selenium toner - you and apparently your books say it can be used as a residual fixer test; Doremus, myself and others are certain it's only a test for residual silver.
This:

R.Gould said:
36 Film and paper residual fixer test

indeed seems to be an error if what follows is the suggestion of using Se toner. And again, you can verify for yourself that selenium toner doesn't work as a residual fixer test, the experiment is extremely simple.
And this:

R.Gould said:
Nowhere do Ilford say this is a test for residual SILVER. they say it is a test for adequate fixing. thetests I give is stated to be tests for residual fixer in film and paper.

is also an error, on your part, or shows confusion. I repeat what has been stated numerous times now: residual silver test = test for adequate fixing. residual fixer test = test for adequate washing.
As we see, a mix-up occurs easily and apparently has happened to the authors of your books.

R.Gould · Apr 21, 2021

grain elevator said:
There is no disagreement about HT-2, we all agree it's a residual fixer test, so we could drop that. Contentious is the use of selenium toner - you and apparently your books say it can be used as a residual fixer test; Doremus, myself and others are certain it's only a test for residual silver.
This:

indeed seems to be an error if what follows is the suggestion of using Se toner. And again, you can verify for yourself that selenium toner doesn't work as a residual fixer test, the experiment is extremely simple.
And this:

is also an error, on your part, or shows confusion. I repeat what has been stated numerous times now: residual silver test = test for adequate fixing. residual fixer test = test for adequate washing.
As we see, a mix-up occurs easily and apparently has happened to the authors of your books.

Lets just agree to differ, there are many old and newer books.the 2 I own and others I have read over a long period of time that give S.T as a residual fixer test, admittly all published id the UK, I have personally used ST as a residual fixer test, as have many others.you say an error on my part I say error on your part, we will never agree, as far as I am concerned discussion closed, end of story, I will continue to do things my way,it has served me well for 60 years, as both an amateur and a professional. All this argument over a simple suggestion to help the OP with his apperant problem, not worth the hassle, never again

Doremus Scudder · Apr 21, 2021

grain elevator said:
Doremus, thank you for the definitive summary. In the section about selenium toner you write "it doesn't stain things as readily as silver nitrate" - that's somewhat confusing as it isn't an alternative to silver nitrate (HT-2), but to sulfide (ST-1).

I was referring to the tendency of silver nitrate to stain everything it comes in contact with (fingers (gloves), sinks, trays, and just about anything else) permanently black. I wasn't referring to the test stain. Selenium toner is easier to clean up after if there's a mishap.

Best,

Doremus

Doremus Scudder · Apr 21, 2021

Richard,

I'll wait to post again till after I receive my copy of Creative Elements and check it out.

Doremus

Doremus Scudder · Apr 27, 2021

Following up on the above.

I received my copy of Creative Elements by Eddie Ephraums today. My copy is paperback, distributed by Amphoto. published by 21st Century Publishing Ltd. in 1993.

I won't comment on the merit of the author's photography except to say it is not my taste. It is the section on technique and methodology, which comprises the second half of the book that I'll address. This "Technical Section" takes up just about half the book and contains lots of useful information about all aspects of black-and-white film exposure, processing and printing, albeit focused primarily on 35mm photography. I find the information given to be a summary and condensation of information from many sources, most notable Ilford and Kodak, however without much in the way of documentation or citation of sources. While I wouldn't go so far as to call it "The Bible" on black-and-white technique and processing, I generally find the information to be accurate, up-to-date (as of the time of publication) and helpful.

The only glitch seems to be in the section in question about testing for residual hypo that initiated the exchange between Richard (R.Gould) and myself. This appears on p. 146 in my copy. Let me make it clear here that I believe that the information in this section of Creative Elements is wrong. It seems to be a condensation of information from Kodak and the alternate selenium test was simply, and erroneously, conflated with the test for residual hypo when it should have been listed as a test for residual silver. All other sources that I have access to, including technical publications from Kodak and the Kodak books of formulas, the Darkroom Cookbook, and some others, give the selenium toner test as a test for residual silver.

To quote the book, from the section on "To test for":

"ii) Residual thiosulphate (hypo) levels in the image:
a) apply Kodak HT2 test (formula 35) to the white print margin and check the stain, if any, under tungsten light, comparing it with Kodak's Hypo Estimator colour chart. It should be lighter than the first cream-coloured patch.
b) apply selenium toner (formula 36) to the margin as for a) above and note and stain once blotted off.
In either of these tests, anything more than a pale cream stain requires longer washing to reduce thiosulphate levels to the 0.01g/m2 level. Daylight should not be used to check the colour of these tests, as it may 'artificially' darken the stain." (p. 146 - emphasis added)

Again, the recommendation to use selenium toner to test for residual hypo (thiosulfates) as a test for adequate washing is an error here. It is unfortunate that this misleading information appears in an otherwise sound description of processing information. For those that have seen and followed this mistaken advice, it is worth noting the error and making the appropriate changes. I refer anyone interested to the Kodak book of formulas I cited above. Kodak is presumably the source for the information in this part of Ephraums' book (note the mention of the HT-2 test), and they state clearly that the selenium test is for residual silver, and a substitute for the ST-1 test.

Best,

Doremus

Question regarding poor print wash

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