platinum palladium processing chemistry in europe

[babak]

Koraks

I wonder if you have a list of chemicals in weight and dilutions that you make up that you could let me have a look at to see if it would be possible?

Thanks

[koraks]

Well, I don't do Pt/Pd, but some other processes (mainly cyanotype, Van Dyke brown and carbon transfer), so I'm not sure if my data would suit you. I just mix my chemicals in accordance with the recipes I find out on the internet.
E.g., for Van Dyke brown I use a sensitizer consisting of 9% ferric ammonium citrate, ca. 3.8 % (probably closer to 4%) silver nitrate and 4% tartaric acid.
For cyanotype, I currently use a mixture based on Mike Ware's writings, consisting of equal amounts of 10% potassium ferricyanide and 40% ferric ammonium oxalate, with one drop of 40% citric acid and one drop of 2% dichromate solution added per ml of sensitizer.
For Van Dyke brown, I also use a gold toner mixed along the lines put out here: http://www.alternativephotography.co.../vandyke-notes
I also use an iron blue toner for Van Dykes for which the recipe currently evades me, but it's along the same lines as the classic cyanotype recipe.
All of these are fairly easy to mix at home. I use an inaccurate kitchen scale (1g resolution) that I use to make concentrated stock solutions of the different chemicals I need in a mix, and then mix the stock solutions in appropriate ratios and add water (if necessary) to reach the final desired dilution. It takes some thinking through and some simple calculus, but by no means rocket science.

If you're intending to do Pt/Pd printing, I would recommend starting with something cheaper first (preferably Van Dyke brown) to get the hang of contact printing and once you have the basics down, move up to a process that will set you back €5 - €15 per print...

[babak]

Thanks that is good advice,
I am a little ignorant though, when you say a solution of 9% for example, how do you actually work that out? is that 9g in 100mls of water?

Babak

[koraks]

You're welcome! Yes, solutions are usually given in weight/volume in photography, so a 9% solution would be 9g in 100ml of solution. In practice, I simply add 100g of water to 9g of dry material (since water is 1g/ml anyway) or I add 100ml of water to 9g of material and accept the minutely larger volume as an inaccuracy that drops away against the variations brought along with all the other inaccuracies I build in to my workflow So easy answer: yes, 9% would be 9g in 100ml.

[Barry Wilkinson]

Hi babak,

You may find some of what you need from this UK supplier

http://www.wetplatesupplies.com/


Barry

[Pete Watkins]

Barry,
Many thanks from me. Silverprint are letting us down in a big way and their prices have shot up.
Pete.

[Emmanuel BIGLER]

An address in Eastern France : Disactis
http://disactis.com/store/fr/

[ron]

Koracks. I have to correct you. For a 9% solution dissolve 9gr in say 70ml distilled water. When everything is dissolved. Fill with distilled water to 100ml. Because the solid have volume to. Effective you use less than 100ml distilled water.

[koraks]

Like I said, it'll introduce a very small error in the range of at most a few % on the total volume. I accept this in my workforce as I don't have the glassware anyway that lets me top up to exactly e.g. 100ml with a smaller error. But you are certainly correct and if you want to be as precise as possible, your method is the right one.