U of S | Mailing List Archive | alt-photo-process-l | Re: Ruined 3rd tricolor gum print! Grrrr...

Re: Ruined 3rd tricolor gum print! Grrrr...



My first thought, without seeing the thing myself, is that you're using too much thalo; the flaking, the uneven coating, the overwhelmingness that you describe (though I might be understanding that different than you're meaning it) all suggest too much pigment. I could be wrong; I'd have to see it for myself to know for sure.

In my experience, a cyan-last order works best, because with the yellow and red already down, you can watch the color balance and tonality while developing and take it out when it's "right;" in other words it's easier to get it right on the first try printing cyan last.
Katharine



On Sep 22, 2008, at 6:34 AM, Loris Medici wrote:

Hi all,

I'm trying tricolor gum printing using plain paper negatives.

I start with yellow (Schmincke 208 Aureolin Modern PY151 Benzimidazolone),
then I print the magenta (Schmincke 351 Ruby Red PV19 Quinacridone Red)
and everything (tonality, smoothness, color) is good & nice up to here...

As the last layer, I print the cyan (Schmincke 479 Helio Cerulean PB15:3
Phtalocyanine Blue) and somehow it's too overwhelming, very uneven, and it
flakes like crazy!

Pigment amounts are as following:
1. Yellow, pea sized, into 3.75ml gum + 3.75ml dichromate
2. Magenta, lentil sized (read as: half of yellow), same as 1
3. Cyan, lentil sized (same as magenta), same as 1

Exposure times and dichromate amounts are the same for all three layers
(15mins., 20% ammonium dichromate). I use automatic development for 30
minutes, sometimes a little longer according to how it looks.

I don't know why I'm having this problem but will try to (all together):
a) Print in the opposite order (1. Cyan, 2. Magenta, 3. Yellow)
b) Use even less cyan pigment to match the color intensity of previous layers
c) Try to not panic while struggling to coat an extra even cyan layer...

What can you say? Any ideas on why I'm stuck that way?

Thanks in advance,
Loris.