Tag: Gum Bichromate
Creating a curve
Gum Bichromate Printing: Squeegeeing gelatin
June 3, 2019
ongoponton asked: Hey Toni i saw the sections of Christopher James book and Christina Andersons book that included you.i found you on medium and read all of your posts. I am just doing some tricolor tests usually jump right in to the most complicated and work backwards. I just had a question about your digital step wedges did you custom make these or are they available online someplace?
I make my own step wedges. Send me an email at firstname.lastname@example.org and I can email you the wedges I’m using
RGB vs CMYK negatives
March 31, 2019
paulivanushkaphotography-blog asked: when working with cmyk print, at what point in time do i change my finished file to cmyk? or do work post prod in cmyk if iam going to mske a cmyk gum print?
I only use RGB, but if your going to make CMYK negs, I think perhaps you should work in CMYK mode from the start or better yet convert to CMYK right before you Multichannel.
Difference between Ammonium and Potassium Dichromate
March 31, 2019
darkroom-dave asked: Hey Tony, I was curious about the differences between potassium bichromate and ammonium bichromate and why you use the later.
I find the Potassium Dichromate doesn’t dissolve as well as the Ammonium Dichromate. Apparently, Potassium Dichromate produces less contrast but I can control the contrast in my print by varying the ration of Gum Arabic to Sensitizer using Ammonium Dichromate.