Cyano-vanDyke ... finding a use for used B/W fixer - did i find a new process? or is this an existing process variation?

Trying to find a new process using used hypo-fixer. This should contain silver and I have been working many experiments to see if i can release that again for some type of VanDyke print. Adding it direct will result in fainter blue.
-> let me know if I have found a new process or if this is something existing under a different name already.

Finally tried following:

- a few ml of used fixer
- add some Copper Sulfate (not much)
- wait till it has reacted (it will become brown or dark)
- add same volume of 25gr/100ml concentration Ferric ammonium citrate (same as used for Cyanotype.

Paint on paper or linen
- let dry for short time

Expose in UV or Sun (about same time as normal cyanotype.

- The paper will have before exposing almost white / light green color
- after 3 minutes it will turn yellow
- after 10-50 minutes it will become coffee with milk color.

Contrast seems to have more gradations (see the middle grass halm)

Development:
- I rinsed it in water with a drop of vinegar (pH of my water is 8 so i have to bring it down slightly)
- Dry.


^any tips or suggestions for further experiments welcome.

Looks very interesting. What is the role of copper sulfate in this?

:Niranjan.


P.S. Welcome to Photrio!

A few thoughts...

Along the lines of Niranjan's comment... what happens if you leave out the copper sulfate? Additionally, which copper sulfate? Copper(II) sulfate is the common compound but Copper(I) sulfate is also available. Lastly, what was your rationale for adding the copper sulfate?

You say that the addition of copper to used fixer results in a dark brown solution. However, you do not say what happens when you add the ferric ammonium citrate to the above solution. Please tell us what, if anything, happens at this stage.

I do not think that this process has anything to do with cyanotype other that you use ferric ammonium citrate. Cyanotype refers to a process that produces Prussian Blue not to a process that uses ferric ammonium citrate. There are a number of processes, including as you suggest, VanDyke Brown, that use the latter compound.

My feeling is that you have basically 'discovered' a variant of VanDyke Brown.

Is the print you have made stable after washing with acidified water? In other words, what happens if you take a washed and dried print and put it out in the sun for a few hours or longer?

Washing multiple times with acidified water is good way to remove residual iron from the print but I doubt a single, short rinse will be effective in this regard. Furthermore, I wonder if such a rinse with remove all of the non-image forming silver, but since you were starting with used fixer (i.e. silver thiosulfate) rather that a silver halide you might be OK in this regard.

I hope that these comments are useful to you. I applaud your sense of adventure/experimentation!

--- Frank

Have you tried and found out what happens when you use fresh/unused fixer (sodium thiosulphate) instead of used fixer (sodium thiosulphate + silver thiosulphate complexes)? This will reveal the role played by silver in your method.

Have you looked at a process called Cuprotype? It uses copper sulphate and ferric ammonium citrate as the sensitizer. If you take out fixer from your sensitizer, you get Cuprotype senisitizer. I wonder what results you would get with your sensitizer if you follow the developing steps of Cuprotype. This will reveal the role played by copper.

Have you tried first mixing copper sulphate and ferric ammonium citrate (along the lines of Cuprotype senisitizer) and then adding used fixer to this mix? Would the result be different if this path is taken? This will tell whether the reaction between copper sulphate and fixer that resulted in a brown solution is necessary for your process or not.

It could be my eyes, but the final developed image seems to lack the fine details that are in the intermediate images. Is this what you also find in the prints?

fgorga said:

I applaud your sense of adventure/experimentation!

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+1

fgorga said:

My feeling is that you have basically 'discovered' a variant of VanDyke Brown.

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That's what it looks like. Given the processing, it will be poorly fixed, or virtually not fixed at all, and is likely to darken and then fade.

Raghu Kuvempunagar said:

Cuprotype? It uses copper sulphate and ferric ammonium citrate as the sensitizer.

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I would expect the printed out image to be more pink than yellow/orange/brown. See also the example on the page you quoted.

Raghu Kuvempunagar said:

the final developed image seems to lack the fine details that are in the intermediate images.

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Typical for Van Dyke Brown is the pretty drastic changes the print goes through upon processing, and the rather steep S-curve. Testing with a proper negative would be the first step ahead.

fgorga said:

I applaud your sense of adventure/experimentation!

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Certainly, and it's not often that such experimentation amounts to anything at all, so it's a pretty significant result!

nmp said:

Looks very interesting. What is the role of copper sulfate in this?

:Niranjan.


P.S. Welcome to Photrio!

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Indeed very interesting and yes it was my very first post. I have been reading and getting information though for many years already from Apug and Photrio.
I have been trying on and off to get some use out of the used fixer which is by the way normal Ilford Rapid fix in 1 to 4 dilution and was used for many bw films to clear.
I was not able to get direct results but very faint image after long exposure in the sun. The idea for the copper sulfate was because it sounded like a good combination. After the try I found some article about thio complex and copper sulfate also.
article thio and copper sulfate

Thank you already for all the comments, let me try to answer the questions and good stuff for some further experiments.

- the used fixer = IlFord Rapid fixer in dilution for film 1:4 and used for many films
- the copper sulfate is the normal blue crystaline CuSO4.5H2O
- after mixing in the Ferric ammonium citrate the color is dark green
- after painting this on paper it is light green and does not darken later if kept in dark
- the paper with emulsion seems to loose its sensitivity after some days, only slight darkening then is seen while exposing in full sun
- the rinsed prints do not seem to change (yet after 1 week) I have not tried to put one of them in full bright light yet neither.
- i have "developed" on of the sample in diluted Potassium ferricyanide - which makes it a mix between the brown and blue, with some pink (see below the picture with the feathers)
- regarding sharpness, I think it is very sharp, see the middle grass in detail, it shows nice tonal range and lots of detail.
- indeed it took many tries to get something that is of any use...

My goal was to have a photographic use of using the used fixer for the silver, but yes i should try if taking unused fixer has the same result, same for leaving out the copper sulfate.

About the Cuprotype, if have tried copper sulfate + Ferric ammonium citrate but this did not really do much, perhaps at most a faint picture. I did not pursue that but will have a look at that again now that i have read-up on it a bit.

below some links to the results sofar which I like.

Thanks again for all the comments and suggestions!

Jan de Jong said:

I found some article about thio complex and copper sulfate also.
article thio and copper sulfate

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Is the role of copper sulphate in this process to regenerate silver thiosulphate by oxidising the precipitated silver in the used fixer? And is silver thiosulphate acting as the substitute for silver nitrate? So, is this a variant of Vandyke process as others have suspected?

Raghu Kuvempunagar said:

Is the role of copper sulphate in this process to regenerate silver thiosulphate by oxidising the precipitated silver in the used fixer? And is silver thiosulphate acting as the substitute for silver nitrate? So, is this a variant of Vandyke process as others have suspected?

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I think it's safe to say no one knows these answers yet.

No answer yet, i am making test prints with all the combinations, will make some scan of the unwashed prints, then wash with water and scan again.
Sofar it looks like the used fixer only has a small contribution to darker brown. Any other combination ie with Cu without etc all produce brown photo reaction in different shade.
The test prints are all 30 minutes exposed with UV light, for a test that should do.I should have some results tomorrow.
The tests are based on combinations of
new fixer, used fixer, copper sulfate, Ferric ammonium citrate and as bonus iron-sulfate.

While we are conjecturing, mine off the top of my (non-chemist) head is:

Ferrous from exposure reduces Cu(2) to Cu(1) which is similar to the Cuprotype referenced above. In that method, the ammonium thiocyanate is used to make insoluble Cu(1) thiocyanate which is subsequently converted to red copper ferrocyanide by reaction with potassium ferricyanide. In the current case, presence of thiosulfate may be resulting in Cu(1) thiosulfate or further, on decomposing, to copper sulfide or forming some other insoluble colored complex.

Or something like that...

In such a scenario, perhaps silver is not playing too much of a role. So it would be more like a cuprotype and not like a VDB. I would use pure sodium thiosulfate / copper sulfate / FAC as a sensitizer and see if it gives a similar image.

Then again I could be way off.

>>>
Copper sulfate has an interesting relationship with thiosulfate:


<<<

:Niranjan.

Jan de Jong said:

Sofar it looks like the used fixer only has a small contribution to darker brown. Any other combination ie with Cu without etc all produce brown photo reaction in different shade.

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If fresh/unused fixer worked well in your method, then it rules out the role of silver as fresh fixer doesn't contain any silver in it. However, if fresh fixer worked well even without copper sulphate, then it makes your method even more intriguing!

Jan de Jong said:

My goal was to have a photographic use of using the used fixer for the silver

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Precipitate out the silver and dissolve (TAKE THE NECESSARY SAFETY PRECAUTIONS) in nitric acid. Recrystallize and use the silver nitrate for whatever you fancy; photography, mirror coating, etc.
But...you'll find that the amount of silver in used fixer is so low that it's not really worth bothering with it. This is also the reason why, even if you would find a chemical means to make it work in a meaningful way in printmaking, used fixer will never contribute much density. There simply isn't a lot of silver to work with per volume of liquid.

If you for some reason don't want to dispose of used fixer as it is, precipitate out the silver, filter, and discard the liquid. The remaining solid/sludge you could dispose of in a responsible way of your choice. This is a relatively low-effort way of separating out most of the nasty bits. Then you'll have your hands free to truly enjoy alt. process printmaking in a reliable fashion without being bugged by the little demon that says you should be doing with that used fixer jug...

koraks said:

truly enjoy alt. process printmaking in a reliable fashion without being bugged by the little demon that says you should be doing with that used fixer jug...

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I didn't get the impression from OP's posts that he is bugged by used fixer disposal. My understanding is he wanted to test if used fixer can be used as a silver source in place of silver nitrate in Vandyke-like process and arrived at a process that gave him interesting results. The process might not be perfect and not well understood yet, but is of primary interest to OP than fixer disposal. An integral part of enjoying alt process is experimenting and learning from the results of the experiments. I see nothing wrong in OP's approach.

Raghu Kuvempunagar said:

I see nothing wrong in OP's approach.

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There's nothing wrong with it, there's just a chance that it's a red herring, as you pointed out in your previous post. I'd eliminate that first.

But I do think that the rationale 'let's do something with used fixer' is..well, not necessarily a productive one. It's not 'wrong', but it's not 'right' either.

Jan de Jong said:

Trying to find a new process using used hypo-fixer. This should contain silver and I have been working many experiments to see if i can release that again for some type of VanDyke print.

Click to expand...

Can used fixer be a viable alternative to silver nitrate as a source of silver is a perfectly valid question to ask and explore. Particularly so because not everyone wants to handle silver nitrate. Systematic testing will provide unambiguous answer to the question and in the process OP might also be able to find out why his process and its variants are giving him the results he's getting.

I'm not saying it isn't interesting. But as a realistic means to do something useful with used fixer, let alone a way to circumvent using silver nitrate (you really lost me there), I don't think it's going to amount to anything. Again: it's interesting in its own account, but let's not make it into something it's just not going to be. All I'm doing is instill a tiny bit of realism into the whole thing, not saying it shouldn't be done or anything.

If OP is thinking that his method is a realistic alternative to used fixer disposal, which I doubt, then a simple calculation will convince him that it is not. His process needs only a few ml of fixer for making the sensitizer and to consume even one litre of used fixer, he would need to coat hundreds of sheets if not thousands.

If OP is thinking that used fixer is a realistic alternative to silver nitrate in VanDyke process, systematic testing can prove or disprove the hypothesis. Based on his posts, I find that OP is not averse to putting his hypothesis to testing and revising his opinion based on the findings. It was in this sense I wrote earlier that there's nothing wrong in his approach.

I agree with that!

Some result with different combinations after 30 minute UV lamp exposure and the image below after wash in water with drop of vinegar while drying in the sun. This drying in the sun should show if further fading or coloring takes place. (which was not the case)

note the order of the pictures is not the same. Once dry and darkened (if) i will add full description. top row nr 4 and 5 contain the used Fixer corresponding bottom row 2 and 1.
Since for the test I first was using an inkjet negative but found density not enough on the later tests i added a straw which is having more density.
My conclusion for now, the Rapid fixer used or new does work with all combination. It stays on the paper after washing.
After washing the colors do not darken or fade in the sun. (about 2 hours exposure during drying)
When the used fixer used with copper sulfate it does seem to leave darker image and retaining more details after washing.
From what i have read in the past there is only 1-4 grams of Silver in 1 Liter of used fixer so that would magnitude lower than the normal vanDyke recipe in any case.
So what is forming the brown color on the paper?
- washing with water seems to make it somehow lightproof (short term at least)
- washing with diluted Potassium ferricyanide as first wash - gives blue Cyano color but with pink/copper colored highlights
- washing first with water, then leaving it in Potassium ferricyanide, changes the whole print to pink/copper colored print - this can still be toned darker with green tea.
The prints containing some silver seems to be sharper (detail scans to follow)
So overall i think some Iron Sulfur and perhaps Copper and traces of Silver on the paper. What is good that it stay and does not rinse off. (Specially those containing the used Fixer)



thank you all for your contributions. Some end point for me would be to have some stable brown print and it seems the used photo fixer can help with that. Would be nice to have some not toxic way to darken the overall print.

Jan de Jong said:

So what is forming the brown color on the paper?

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My guess would be an oxidation product of your ferric citrate sensitizer. Basically a fancy form of rust.

Jan de Jong said:

Some result with different combinations after 30 minute UV lamp exposure and the image below after wash in water with drop of vinegar while drying in the sun. This drying in the sun should show if further fading or coloring takes place. (which was not the case)

note the order of the pictures is not the same. Once dry and darkened (if) i will add full description. top row nr 4 and 5 contain the used Fixer corresponding bottom row 2 and 1.
Since for the test I first was using an inkjet negative but found density not enough on the later tests i added a straw which is having more density.
My conclusion for now, the Rapid fixer used or new does work with all combination. It stays on the paper after washing.
After washing the colors do not darken or fade in the sun. (about 2 hours exposure during drying)
When the used fixer used with copper sulfate it does seem to leave darker image and retaining more details after washing.
From what i have read in the past there is only 1-4 grams of Silver in 1 Liter of used fixer so that would magnitude lower than the normal vanDyke recipe in any case.
So what is forming the brown color on the paper?
- washing with water seems to make it somehow lightproof (short term at least)
- washing with diluted Potassium ferricyanide as first wash - gives blue Cyano color but with pink/copper colored highlights
- washing first with water, then leaving it in Potassium ferricyanide, changes the whole print to pink/copper colored print - this can still be toned darker with green tea.
The prints containing some silver seems to be sharper (detail scans to follow)
So overall i think some Iron Sulfur and perhaps Copper and traces of Silver on the paper. What is good that it stay and does not rinse off. (Specially those containing the used Fixer)
View attachment 311043
View attachment 311044

thank you all for your contributions. Some end point for me would be to have some stable brown print and it seems the used photo fixer can help with that. Would be nice to have some not toxic way to darken the overall print.

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Thanks for sharing the progress report.

One suggestion I would have is to be much more specific with details of how the experiments are carried out including amounts and concentrations (not qualitative like "little" or "some" etc,) order of addition, what kind of fixer you are using - acidic or basic, what kind of paper you are using, etc. If someone else is going to try and duplicate any of your experiments, they would need those details.

:Niranjan.

@niranjan You are right would be nice to have all details, but i am still direction finding.
- paper is 300gr 20 sheets Artists Aquarell from Action less than 2 Euro - this paper is extreme good for Cyanotype. Second the linen sheet is similar product from Action and is 10 sheets for 2 Euro. Emulsion sticks a bit less good but results with this type of process are a bit darker brown (see earlier posted picture) Paper if dried slow - is fully flat, no need for flattening
- Fix is acidic as it is Ilford Rapid Fix. 1-4 film stock solution
- Cupper Sulfate is added in excess. Important in the samples of my test I added all in the mix, but in my initial experiments I first added Copper Sulfate in a reaction tube, then added used Fixer and decanted the dark mix without the residu from the bottom of the tube.

When I have time next weekend I will make a summary but basically all combinations give some results, nothing washes off. Now it is a matter of getting the concentrations up and in right mix to have the dark prints that I had in the first session. There the exposure was also longer 2 hours of bright sun.

I have added detailed scans on flicr Experiments

small explation for the codes on the picture and naming
Cu = Copper Sulfate
uF = un-used Ilford Rapid Fix
F = used Ilford Rapid Fix
Old mix= initial mix but week old and dried up, i added water.
FeSO4
G = Green Ferric ammonium citrate
R = Potassium ferricyanide (red)

My interest is the photo action of light on metals (salts) specially Iron, Copper, Silver

nmp said:

I would use pure sodium thiosulfate /

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Indeed that is what i have to try next, as it would allow to get the concentrations up and under measurable control. As to the used fix, that is an undefined variable as to how much silver is in that used fix..

Jan de Jong said:

Indeed that is what i have to try next, as it would allow to get the concentrations up and under measurable control. As to the used fix, that is an undefined variable as to how much silver is in that used fix..

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So the curiosity got the better of me last night and I thought since I have all the ingredients at hand, why not try this myself. And I must say I was quite pleasantly surprised.

Here is what I did:

I mixed FAC, Copper sulfate pentahydrate and sodium thiosulfate pentahydrate in the dry weight ratio of 1:0.6:0.36 (I screwed up the measurements – this exact ratio was not my intention but decided to use it anyway. I did want to keep the copper sulfate in molar excess to thiosulfate which did happen to satisfy here.) The total solids of the concoction turned out to be about 19% (w/w) in dist. water. The order of mixing was first add copper sulfate solution to FAC solution, mix, whereby the solution became darker shade of emerald green from pale green color of FAC solution. Then add the sodium thiosulfate solution. The color remained the same. No precipitation. (As a matter of fact, this solution stayed in this condition even overnight without any change which was contrary to what happens when copper sulfate and thiosulfate are added by themselves.)

Rod-coated a 1”x7” strip of COT 320. Paper took the solution quite nicely. Air dry 10 minutes, followed by 8 minutes in convection oven at ~40 C.

Exposed for 40 minutes with the Stouffer’s (not the eating kind....) on top. There was a strong orange color print-out as it came out of the UV box.

Washed in tap water for 7 minutes with 4 changes of water.

Heat dried for expediency. Attachment #1 shows how the strip looks at this point.



40 minutes exposure was certainly required as the Dmax barely reached at the step #1. So it’s kind of slow. Compare that to needing about 25 minutes for cyanotypes in this UV box and about 8 minutes for salt prints. The Dmax is not that great as might be required for a good pictorial process. So improvement would be needed. However, Dmin at Step #21 is nearly paper white (just a bit darker than the bare paper, perhaps a citric wash step might help) - which is good because for any process, new or old, it is the most difficult characteristic to achieve. If I have to eye-ball, I would say there are about 18 steps worth of DR in the print (each step is 0.7 stop.)

On the face of it, this process looks very similar to Jim Patterson’s Cuprotype referenced above – the difference here is while in the latter the developer is the ammonuim thiocyanate applied as external step, the same in this case seems to be in-situ within the sensitizer in the form of sodium thiosulfate.

So the question is if the image is some form of copper compound facilitated by UV induced ferrous ions, will it react with potassium ferricyanide to form red copper ferrocyanide? Answer in a future post.

Need real chemists to chime in with their explanations....


:Niranjan.