Ultramarine is not a good blue for a nice array of greens IMO. Yet your problem is different from choosing a particular pigment. Go back to Photoshop and examine your RGB chanels (inverted) and compare them to your negatives. Did you by chance switch G and B separations? Does the B (yellow pigment) separation need slightly different curve or longer printing time. Check that your B negative is not too dense in the green part and you can actually print yellow through it. Can you post original colour image and the cyan/yellow print?
Marek
> Date: Tue, 10 Mar 2009 10:47:57 -0700 > From: cryberg@comcast.net > Subject: can't get green tone in gum--help please > To: alt-photo-process-l@usask.ca > > Folks, I've made one nice tri-color gum (many months ago) and > thrown away scores. The image I'm trying to print is a café scene with > green only in the tablecloth. The rest of the image is warm--mostly pale > cream yellows and red brick. There is a woman in a blue dress walking away > from the camera. I like the image. My first coat is Daniel Smith French > Ultramarine. The second is Daniel Smith Hansa Yellow Medium. I have not > yet done the Magenta. The overall cast of the image is clearly cyan though > there is yellow too. But no green. When it dries, I'll do the magenta, but > I just can't see the image working without that small green cloth. Any > advice? >