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Sistan available?

H. James Wolf

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Feb 25, 2008
Messages
34
Format
35mm RF
For several years, I have been using Sistan as a final bath for Ilford MG warmtone RC paper. Now I'm getting down to my last bottle, and I can't find it anywhere. I know Agfa has gone, reappeared, and gone again. Is someone else producing Sistan or the equivalent. (I also use selenium and want Sistan to supplement it, not replace it.)
 
fschifano said:
I'm not a Sistan user, but I'm curious what it is. If you have a formula, please post it.
Click to expand...

Frank

Usually the MSDS sheets are not very revealing, because they list a wide tolerance for all the ingredients. This is not the case with Sistan for some reason. I'm in the process to obtain the chemicals and will give it a go.

COMPONENT NAME
/CAS NUMBER CONCENTRATION
-------------------------------------------------------------------------------
Water
7732-18-5 70-75 %
Potassium thiocyanate
333-20-0 15-20 %
Polyoxyethylated Octyl Phenol
9002-93-1 5-10 %
-------------------------------------------------------------------------------
 
That is basically an average of a 17.5 % solution of KSCN and about 7.5% Photo Flo or the like. How dilute should it be for use?

PE
 
At some point in its final few years of production either the concentration of Sistan was changed, or Agfa changed its mind about how to set the balance of risks between over- and under-concentration.

In any case, an old-old-stock bottle that I have says to dilute 1+39, while late-production bottles labeled "Sistan New" say to dilute 1+19 for use.
 
H. James Wolf said:
(I also use selenium and want Sistan to supplement it, not replace it.)
Click to expand...

I suspect there is not a single study on that combination for that purpose.
With fully toned prints, you'd be hard pressed to demonstrate the need for
further protection... how will you know your actions are not just artifical sweetener or even plain sugar on top of Fructose?
 
H. James Wolf said:
I know Agfa has gone, reappeared, and gone again. Is someone else producing Sistan or the equivalent.
Click to expand...

To my understanding Sistan is still produced on special order by the former Agfa processing chemicals plant in Germany.

However due to brand name licensing issues the name may have changed. One new brand name is "AgStab".




Concerning the alleged death of Agfa see here:
(there was a url link here which no longer exists)
 
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Ray Rogers said:
I suspect there is not a single study on that combination for that purpose. ...
Click to expand...

I've started a long-term accelerated test on this 10 years ago. So far it only tells me is that not toning is not an option, even with otherwise proper processing.

Ray Rogers said:
... With fully toned prints, you'd be hard pressed to demonstrate the need for further protection... how will you know your actions are not just artifical sweetener or even plain sugar on top of Fructose?
Click to expand...

Couple of points here:

Prints are rarely 'fully' toned, because that would result in a significant hue shift. All selenium-toned prints, toned in 1+19 or 1+19 for several minutes, are partially toned, and consequently, partially protected. That's why combination and split-toning works. This is less so the case with direct sulfide toning and only indirect sulfide toning gets close to 'fully' toned.

Also, toning (sulfide, selenium) and silver stabilizing (Sistan) are not the same thing. Toning is a conversion of silver into inert silver compounds such as silver-sulfide or silver-selenide. Stabilizing converts residual silver halides to inert silver complexes, and while remaining in the emulsion, it converts mobile silver ions, created by pollutants attacking the silver image, to stable silver thiocyanate during the print’s life. The resulting silver compounds are transparent, light insensitive and chemically resistant thus protecting the image beyond toning. Silver image stabilizers are not a replacement for toning, but offer additional image protection.

In short, toning and Sistan are not the same thing. Sistan was developed to help to stabilize RC prints. With FB prints, freed silver ions are not trapped by the plastic layer and are able to escape before they can do any harm (no Sistan needed).

With RC prints, I can see a reason to tone and stabilize, but the test mentioned above has not shown this need so far.
 
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How did you achieve acceleration in your test?
 


I got another MSDS, seemingly the latest:
There it says: Potassium thiocyanate 9.5 %


This seemingly goes along with the changed advised dilution rate for the working solution in the latest version as indicated here:



So Agfa seemingly just reduced the concetration of their newer concentrate.
 
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AgX said:
How did you achieve acceleration in your test?
Click to expand...

Typically extra doses of Ozon, UV, heat and humidity, but who knows what will attack our prints in the future. Accelerated tests are always a compromise and never 100% reliable.
 
H. James --

I purchased my most recent bottle of Sistan from Freestyle.

Like you, I use selenium toner and Sistan with my Ilford Multigrade RC prints. I usually tone only slightly in selenium, KRST or Ilford at 1:9 for between 1 and 2 minutes, depending on the print. This gives a slighty improved D-max without bringing down the highlights, with just a barely perceptible change in hue; then I wash and follow with Sistan. My prints are then hinge mounted, matted and framed with acid free materials according to what I understand to be archival protocols.

I would like to think that I do high quality work, both artistically and technically, but I do it with RC paper. I know that there are strong feelings among many that only FB papers can be used for work to be considered the best, but right now my lifestyle is such that I feel I must sacrifice the extra time commitment required for FB processing and use RC instead. I know there were significant problems with the first RC papers introduced in the 70's, but they have since been greatly improved and it would seem that only time will tell how modern RC papers, partially toned and stabilized with Sistan, can compete with FB for longevity.

Regards,

Dave
 
RalphLambrecht said:
I've started a long-term accelerated test on this 10 years ago. So far it only tells me is that not toning is not an option, even with otherwise proper processing.
Click to expand...

Nice to hear of your study, Ralph.

Not everyone uses Kodaks Seleniun Rapid Toner nor follows that dilution;
uses and expectations do varry.

If you are saying that 1:19 dilution of KRST for any toning duration at any temperature will never yield "full conversion" I am not so sure...
I use my own (non thiosulfate) seleniun toner.

I don't know how you determined that silver thiocyanate was
light insensitive, but that seems to be somewhat of an exaggaration.

Also, you mentioned that with fiber base papers,
the silver ions can escape before they do any harm...

hummm...
Escape? Where to?

Also, calculating the correct amount is fairly critical;
Too much thiocyanate is harmful... probably more so than it's total disuse.

(I look forward to reading your writeup of the completed tests. Ten years ago, I also looked into this but concluded there was no good way to quantify the necessary amount and thus that no real and consistant improvement over good processing and final toning could be expected. It will be nice to read something new on the subject.)
 
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Dave Martiny said:
I know that there are strong feelings among many that only FB papers can be used for work to be considered the best...
Click to expand...

Well, I'm not one of them. Call me a Philistine if you prefer, but I like RC papers and have never had any complaints about any of my really nice prints made on these papers. I especially like the pearl or semi-matte finished RC papers. The glossy ones are just sometimes too glossy.
 
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Ray Rogers said:
... If you are saying that 1:19 dilution of KRST for any toning duration at any temperature will never yield "full conversion" I am not so sure...
I use my own (non thiosulfate) seleniun toner. ...
Click to expand...

Silver-selenide is a very inert compound. Try to bleach prints toned for different amounts of time. Any image fading is a sign for less than full conversion.

Ray Rogers said:
... Also, you mentioned that with fiber base papers, the silver ions can escape before they do any harm...

hummm...
Escape? Where to?...
Click to expand...

Into the fibers. With RC, they are prevented to do so by the polyethylene layer. Sistan was made for RC. For FB it's OTT.
 
fschifano said:
Well, I'm not one of them. I like RC papers and have never had any complaints about any of my really nice prints made on these papers. I especially like the pearl or semi-matte finished RC papers. The glossy ones are just sometimes too glossy.
Click to expand...

FB has inherently a better chance to survive RC due to the missing polyethylene layer and it's sensitivity to UV radiation, but with RC processing errors are less likely than with FB. Take your pick. Aesthetically, many prefer FB over RC. Take your pick. Using RC over FB to save time for the photographer is a bad excuse. Print aesthetics and quality must take priority over saving time. Photography is an art not a race.
 
I used the link to digitaltruth and it showed Sistan, but going to the website but not through the link does not show it - I will call next week. As to Freestyle, they did stock it and, in an email, promised to do so again if they could find a supplier. I will try the other suggestions next week. As to the use, I use RC and am using Sistan based on tests Cetin did in his book - sorry, don't have the title in front of me. So far, it has worked. It may be like snapping your fingers to keep elephants away - you don't know if it works but there aren't any elephants around. Thanks to all for their suggestions.
 
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