The toxicity of ammonium dichromate puts a bit of a potential damper on carbon and gum printing, especially if one want to work in Europe, where availability might soon become a real problem. Ammonium Dichromate can't be shipped by air, its a strong carcinogen etc. the whole bit… What about residual dichromate in the carbon print for instance…. if it is a carcinogen it's only a matter of time before it will be branded.

Well first….. am I right in that statement….. how big a problem is this in real life???? I have zero experience at this point.

There is a process floating around called the The Chiba System.

It use Ammonium ferric citrate as the sensitizer and 0.3 % Hydrogen Peroxide as developer. Both largely non toxic especially compared to Ammonium Dichromate.

Is this process for real or just BS….. Would be interesting the hear what the real pros doing carbon printing here has to say about this.

And how does it effect the quality and archival properties of carbon prints?

See

http://www.google.ca/url?sa=t&rct=j&...bqsJyV9VG5npig