U of S | Mailing List Archive | alt-photo-process-l | Re: Paper negatives- Ink Selection

Re: Paper negatives- Ink Selection

stronger dichromate concentration (saturated PD whereas I use 10% AD) but
his exposure times are about 1.3 stop slower than mines (his 15 minutes
versus my 6:30 - oiled or non oiled negatives I don't remember), which I
find remarkable.

Not to butt in on this dialogue you all are having, but I thought I'd re-remind you that a 10% am di is not equivalent to a 10% pot di--it is faster. I am in a full knee brace and don't feel like hobbling to my desk at the moment to locate the comparison (can you tell I am SERIOUSLY inconvenienced by my condition?) but it was posted to the list a while back by Sandy King, and then I think even by you and Alberto haggling out the percentage. That can account for some of the difference. Also, is it more humid in Turkey? Also, thick vs. thin layers, etc. etc. I find that the way one brushes on a gum coat is probably the biggest reason for success and failure. The thinner the better. But all of that is determined with overlapping the step wedge with the substrate of choice so it might be helpful to send a small strip of your substrate of choice to each other or I probably forgot it was the same stuff didn't I....

With a 15% am di and Pictorico I am using a 6 min exposure.

Guido, I so agree with your "intuitive" way of working with gum. Though I had to get it predicatable first, which I think Loris is working on in his own practice, before I then became loose. In all these years now of doing the practice the way I do I have only had one anomaly, and that was a layer that completely did not expose and flaked off entirely. So I think all the hype about gum being fickle and finicky and difficult is exaggerated once you get your feet firmly planted on the ground.

I have 1 1/2 days next week to teach a class in Missoula MT how to do perfect gums so we'll see if it is possible :) But how the heck I am going to do that when I am in a full leg brace is a totally other story.