Looking for KCN

RBarr

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I'm having a hard time sourcing potassium cyanide for wet plate fixer. Is there a source for small quantities of KCN? I own an environmental consulting company so I can likely buy in bulk (and know how to handle and dispose), just didn't want to spend +$1000 on a kilo.
Any guidance would be greatly appreciated. I did search, but most of the returns were 10+ years old. I haven't posted here yet, but lurk now and again.
Rob
 
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OP
OP

RBarr

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Hahaha, Autocorrect. I work with a company called KCM. Yes....KCN
 

mohmad khatab

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RBarr said:
can likely buy in bulk
Click to expand...

In America and developed democracies, I think you will not be able to get that..
This is the price of urbanization, environmental conditions, and so on.
Available in Egypt, my country sells by kilo.
But despite that, I didn't like to use KCN,, for bleaching. It's a relatively expensive ingredient (from my point of view).
Therefore, I was able to find very suitable and very affordable alternatives.
So, I advise you to tell us what you want to do with (KCN) >>>> Maybe we can suggest you a suitable alternative that you didn't think of.
 

Ray Morgenweck

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Does Mike from Artcraft still sell it? I know John Coffer had a good amount some years ago and sold to people “he knew”. Personally, I almost always used a saturated solution straight hypo. To get the extra step of whiteness with tins or black glass anbros, add 2 grams of potassium nitrate to your 16oz of developer.
 

Ian Grant

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KCN is used in plating and stripping in the Jewellery trade, I know it was possible to buy it over the counter with no questions asked not that long ago here in the UK. Technically supply is supposed to be restricted, and you need to provide evidence of how and why you needed to use it.

Ian
 

koraks

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I'm probably going to make myself unpopular by arguing that it's smarter to just use any old rapid fixer. Why bother with KCN and the difficulties and risks it carries if the benefit is marginal?
Alright, maybe I don't sufficiently appreciate the unworldly beauty of a cyanide-fixed tintype, but the results I got with rapid fixer were similar to what I saw from "KCN artists" to not accept the risks of using KCN instead. Having ether vapor all around was enough of an excitement for me to not bother with additional issues.

mohmad khatab said:
I advise you to tell us what you want to do with (KCN)
Click to expand...
It's right there in the first post: wet plate fixer. Logical alternatives are sodium or ammonium thiosulfate fixers.
 

Ian Grant

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You can use plain Hypo solution, sodium Thiosulphate. You can't use Ammonium Thiosulphate because it's too aggressive and would bleach the image, the Ammoinium salt is a Silver solvent.

When I'm printing and fixing warm tone papers in Ilford Rapid Fixer or Amfix there can be quite noticeable bleaching (lightening) of test strips I've left in the fixer for too long. For similar reasons it's best not to use a Rapid fixer with alternative processes like Albumen prints or Kallitypes etc.

Ian
 

koraks

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Ian Grant said:
You can't use Ammonium Thiosulphate because it's too aggressive and would bleach the image
Click to expand...

Worked fine for me, at 1+10 dilution. It fixes very rapidly, but left the image alone. I used C41 fixer which is near-pH neutral. Perhaps that helped?

mohmad khatab said:
I apologize for my ignorance and lack of knowledge.
Click to expand...

Don't beat yourself up over it; it's OK. See e.g. here:

Three fixer test

Recently I bought Amaloco x-89 rapid fixer as I was wondering if it would work with Collodion. Well it did, and I was surprised by the resul...
collodion-art.blogspot.com

Coincidentally, it also shows a quick test using Amaloco F89 rapid fixer along with play hypo and KCN. I'll leave interpretation of the examples up to you guys, but it matches my experience in the sense that rapid fixer worked a treat for me and I found it way more convenient than plain hypo.
 

nmp

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If anything, it looks like the non-KCN ones are a tad smoother with the highlights seemingly more preserved.

There is also this article:

Say goodbye to cyanide: a less toxic approach to fixing wet collodion plates - AlternativePhotography.com

Elizabeth Graves experiments with Waldack's Formulas for Collodion Positives "Formula No. 1. For Dead-Whites" followed by a sodium thiosulfate fixer.
www.alternativephotography.com

:Niranjan.
 

koraks

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I've had this impression I've not been able to shake off for a few years that in the alternative process arena, there's a tendency to use insufficient fixing as a means to harness contrast and/or preserve density that the image or print didn't really have. It's really just an impression and not so much something I can support with solid arguments, except that several times I found alt. process lore to not be entirely accurate in its strict requirements for things like sodium thiosulfate when the ammonium salt proved to work just fine (i.e. in salt prints, Van Dykes etc.) or as in this case, KCN as a wet plate collodion fixer. I can very well imagine that it's possible to retain a little silver when underfixing a plate, and perhaps KCN works to that effect (or fails to work, rather), which will at some point print out and persist as a mild fog, that 'helps' to lift shadows a bit. All I know is that with a pretty bog-standard rapid fixer, I got very clean plates of good contrast.

Coincidentally, I also find it amusing that at the same time, one person alleges that thiosulfate would etch away the silver on a collodion negative (if anything, this would boost contrast by eating away delicate shadow detail), while another (cited) source mentions lower contrast as a result of the use of a thiosulfate fixer, which would imply that either the highlights are reduced while the shadows aren't (which chemical magic would underlie this phenomenon evades me), or that somehow the thiosulfate fixer would quite severely fog the plate, lifting the shadows (which I can very well imagine if insufficient fixing happens, which is a trap that's a lot easier to fall into with sodium thiosulfate as opposed to the quicker ammonium thiosulfate).

Anyway, these are just musing/ramblings; I currently don't shoot wet plate and thus I'm not in a position to do any back to back testing, and I think it's clear to anyone that KCN-fixed plates somehow never caught me in their web of enchantment. Woe is me!
If I ever go back to wet plate, I don't think I'll actually entertain the thought of using a KCN fixer.
 

Ian Grant

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That test you linked to is interesting, the slightly warmer look with KCN and one of the comments would indicate that there is very slight silver bleaching with both fixers, looking at the examples wet would seem to indicate perhaps very slightly more with the Rapid Fixer. With warm tone papers and freshly mixed Rapid Fixer it's surprising how fast the delicate highlights bleach if left too long, you also lose a little of the warmth. The reason is the finer grain of a warm tone paper particularly with quite short development times, compared to a regular bromide paper, and that's the same with alterative silver based process.

Ian
 

koraks

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I'm skeptical, Ian. The main reason is the lack of shadow degradation in the example shown. If silver bleaching were an issue, it would be the shadow detail that would etch away first. Not the 'delicate highlights' as you said, because those aren't delicate, at least not relative to the shadows.

Ian Grant said:
short development times, compared to a regular bromide paper, and that's the same with alterative silver based process.
Click to expand...

Not all alt. processes are develop-out, and they also are more often than not far more resilient against proper fixing than people would lead you to believe.

Anyway, let's not make this into a diatribe; you've got your experience, I've got mine. For some reason we saw different things and interpreted them differently.
 

nmp

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If kinetics were to play a role, which I suspect it does, I would expect the effect on highlights be more pronounced than the shadows. I notice the same phenomenon in toning a salt print with KRST or a sulfide based toner, for example, where the toner also bleaches but the bleaching is disproportionately more evident in the highlights while little or none in shadows, which may actually show improvement in density.

:Niranjan.
 

Ian Grant

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Yes you're totally correct, I was referring to the silver bleaching of delicate highlights of warm tone prints.

Ian
 

nmp

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koraks said:
I'll take your word for it!
Click to expand...
Assuming this is addressed to me - don't take my word for it...

I showed this many moons ago:


Lower density (red line, 5 min exposure) patch starts getting lighter (RGB value as inverse of density goes up, RH scale) regardless of toner (Kala Namak) concentration. Higher density (40 min exposure, LH scale) gets denser at lower concentrations then also bleaches above ~4% (intrapolated.) I used 0.5% to get the best of both worlds - boosting Dmax as well as the contrast - alleviating some of my problem with less than adequate UV density in the negative.

Since then I have verified with other toners like Morsch M16 and KRST, though in those cases the Dmax boost is not very noticeable, but the divergence is still evident.

:Niranjan.
 

koraks

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Alright Niranjan, that's very interesting for sure, but I do have trouble equating fixers to toners. This of course says very little about the interesting effect of apparently stronger bleaching in the highlights than in the shadows; I've never done any measurements on this, but of course overall bleaching is something we're all familiar with in some cases, I guess. I sure am in the case of selenium toning VdB prints, which did indeed severely degrade shadows - but highlights just as well, in my experience. With gold toner (I generally use a gold thiourea toner) I don't recognize this at all; I mostly see a very pronounced contrast boost as toning runs to completion, with an initial contrast decrease but no clear evidence of disproportionally severe bleaching in the shadows.

Mind you, if you have a high and a low density patch, I think it's kind of obvious that in any bleaching situation, the high density patch will lose a lot more density in an absolute sense. But that would still happen if the bleaching is proportionate to the initial density, see what I mean?
 

nmp

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I only brought up toning because you made a general comment about bleaching: If silver bleaching were an issue, it would be the shadow detail that would etch away first. Not the 'delicate highlights' as you said, because those aren't delicate, at least not relative to the shadows. So I pointed out that in case of silver bleaching that occurs in toning, the experience is quite the opposite. On the basis of kinetics of dissolution, one can explain why that would be so. In the highlights, particularly in warm papers as Ian pointed out, the particles are much smaller and far apart while in the shadows, they tend to be larger and packed closer together. Because of larger surface-to-volume ratios and faster diffusion, bleaching action is favored in the highlights than in the shadows.


Yes, gold is quite different. There is only replacement toning and no pronounced competing bleaching action that seems to be present in both selenium and sulfide toners (so far the ones I have tried.) That's why people prefer it for silver based prints. So as you start toning, the highlights get toned first increasing their density and decreasing the apparent contrast as a result. As toning is continued to completion, more of the shadows come in and the contrast is boosted back up. Here your observation seems to be in agreement with the same controlling mechanism that also explains the bleaching action.


Not always. As I explained above, kinetics of bleaching action can create disproportional outcome between the shadows and the highlights. When we do bleaching of cyanotypes with an alkali, the highlights start disappearing quite rapidly while the shadows lag behind significantly (particularly if using a weaker base) - something that is exploited by many to get a split toning effect when followed up with a polyphenol toner.

In any case, this is how I try to understand, which I am sure is far more simplified/simplistic(?) than it actually is - obviously subject to change with any new information....

Also, this is far OT from OP's original query. So I will rest at that.

Cheers!

:Niranjan.
 

Vaughn

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Thanks. It has been a while since I silver printed w/ warm toned papers...but since I selenium toned and wanted a specific color, being very consistent with fixing seemed to be an important factor.
 
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