The sodium citrate developer is a very safe developer, consisting only of citric acid and sodium carbonate.

The contrast agent used with the developer is potassium dichromate. It is classified as moderately toxic by skin contact and ingestion and highly toxic by inhalation, and a *suspected* carcinogen. You can buy it in solution from B&S which avoids the inhalateion issue. Dichromates are no more toxic than many substances in common use in photography, including hydroquinone and many other reducers, selenium, the ferric salts we use in vandyke and kallitype printing (ferric oxalate and ferric ammonium citrate). If used with the same care we should give all toxic substances used in the darkroom the risks of dichromate are very small, IMO.

Sandy



Quote Originally Posted by Wayne
I've been debating the idea of trying to do some alternative processone of these months/years, and based on what I've read the Van Dyke or kallitype seems like the one to try. I like the color control with kallitype, so thats in the lead. But thanks to a long, rich family history of cancer and general klutziness on my part, I refuse to mess with known carcinogens like those used for contrast control in kallitype. Minor chemical burns, I can probably live with. I'm not going to change my mind, so lets avoid that debate.

Based on my limited understanding, that leaves me either needing to make digital negatives so that I can control the contrast, or making perfect negatives. The former probably isnt going to happen anytime soon even if I wanted it to, so I think that leaves only perfect negatives. So how hard is it to achieve that goal? I realize it will restrict my subject matter somewhat, but if I overdevelop contrasty scenes can I get consistantly suitable negatives for kallitype that dont need chemical contrast control?