Blogging for Thor: Chemical Crossovers

Potassium Dichromate (K2Cr2O7): a rather nasty
but potentially beautiful little chemical

I really enjoy the ability of social media to bring together artists from all across the world. After posting yesterday's blog on the Alternative Photographic Processes Facebook group, I got some wonderful responses from Serdar Bilici, Johannes Schmidt and Mark Osterman. So, instead of sharing some of my own work today, I'm going to be discussing ideas from these fine folks.

Serdar informed me that he had previously made images using silver citrate, silver tartarate and silver carbonate instead of a silver halide. Unfortunately, he did not have any scans of these images, but he did say that he found them either too low in d-max, or too high in contrast for negative printing. Here's a list of what he said he used to create the different silver compounds

Silver Citrate = Silver Nitrate + Sodium Citrate
Silver Tartarate = Silver Nitrate + Tartaric Acid (maybe from cream of tartar?)
Silver Carbonate = Silver Nitrate + Sodium Carbonate (soda ash)

Basically, all that means that silver compounds aside from halides can likely be used to print visible images. I'm going to give these a try most definitely, especially since soda ash and cream of tartar are so easy to get. Sodium citrate is available from the university lab, so I'll be giving that a shot as well.

Mark Osterman discussed with me the fixing ability of potassium iodide. Previously, I had fixed several prints in 5.6% potassium iodide, but not noticed any significant difference in the result from the more traditional sodium thiosulfate fixer. If anything, the potassium iodide leaves a warmer tone in the fixed image, but both fixing processes remove a lot of the color from a salt printed image. Mark says that, in theory, a salt print fixed in potassium iodide should turn yellow as the silver is converted to silver iodide. He also recommended that I find a copy of Records of the Dawn of Photography, which is a published version of Talbot's early notebooks. Unfortunately, that book sells for over four hundred dollars and there aren't any circulating copies in my local libraries. I may be able to visit a nearby university (I'm in friggin Boston) and make scans or notes. I'll have to look into that.

The most interesting conversation, though, was with Johannes Schmidt. He told me that he'd run across some literature a bit over a year ago that suggested adding salts of organic acids to the standard sodium chloride and silver nitrate mixture used in salt printing could alter the color of the print. He mixed up solutions of potassium or sodium compounds of acetate, ascorbate, formate, succinate and tartrate. These solutions were applied along with sodium chloride to paper, which was then sensitized with silver nitrate. He also tested the effects of dichromate, iodine and photographic developer on the silvered paper. There are some truly lovely results, especially from the dichromate. In fact, I'm going to borrow some ammonium dichromate from the university and do some tests of my own with applying it to salt prints.

Who knows, maybe I'll give up on this whole "photogram" thing and just create my images through pure chemistry. Chemigrams are popular, right?