Thanks. He shows 2 options in his book. The first option is just as you have stated, but not using gelatin and dichromate-- rather, using gum and dichromate. He suggests mixing up a gum dichromate solution of 5ml of dichromate (either potassium or ammonium), 10 ml of gum arabic, and 10 ml of water and exposing it to UV for 5 minutes. The other is coating with equal proportions of a saturated dichromate and gum- coat it, let it dry, and expose to UV for 1-3 minutes. This is the version I tried-- then washed it. The other place wheere I saw this mentioned was in Sarah Van Keuren's workbook, but she suggests spreading the dichromate on the paper first, and then spreading the gum as a separate layer on top of that. I'm not sure if it makes a difference (rather than initially mixing them together and then spreading), but on the off-chance it did make a difference, I tried that, too. That didn't work either. I'm guessing the difference is that you're using gelatin and not gum? If you could email me the details that you use, that would be great. Thanks, Marek.
On Apr 7, 2008, at 9:49 AM, Marek Matusz wrote: