hi Loris - have no idea what sumac is or whether it is possible to get here in Denmark....
I have now tried walnut snaps... (walnut in vodka for about 6 months), and it gives a very deep beautiful brown tone - especially in the highlights..
A shame it taste so good... :munch:
Very interesting, Emil. Just by coincidence, last time I stopped at the vintners' supply shop, they didn't have any tannic acid, but they gave me a teabag of oak.
Originally Posted by gandolfi
I'll have to try it out.
I like to use gallic acid to create iron gall ink using the new cyanotype process. I think this is the closest to a black silver print possible with this process. It is my experience that for the redevelopment (after bleach) to use distilled water and freshly mixed gallic acid. The mixture should be used immediately as once the gallic acid oxidizes it will cause the pigment to migrate throughout the paper causing spots, bleeding, etc. If it is fresh, quickly done, and well washed, it will work. If you dally, you will have a problem.
I have done extensive research into the stability of the iron gall ink. Will it last 1000 years? maybe, depending on how it is stored. Do I care? not really. It only needs to last me 75 yrs until I don't care anymore.
I have now submitted examples of my playing around in the galleries...
see here: (oak tree)
and walnut snaps here:
..and now I have tried Walnut. Walnut bark in a bottle - then boiling water on it and let it soak for a long time (mine soaked for at least two days, but I don't know whether that is nessecary..)
Old cyanotype soaked for about 10 min.