Re: gum prints from digital color sepations. (Since the topic has been brought up)

Carmen,

Are you having to print more layers to get the color corrected, or to get
the depth of the print right? If the latter, you need to up your pigment in
your formula. If the former, it is the balance of each color coupled with
exposure, perhaps.

For whatever it is worth, here is my personal gum practice--one of many
possible ways to go.

I have been using M. Graham colors exclusively, it seems (verrry high
quality but inexpensive): Quinacridone Rose (PV19R) and Gamboge (PY110
isoindolinone) on top of a full exposure of cyanotype traditional 2A:1B and
the fact that I am able to get a goldfish to be bright orange and even get
the Clemson University Tigers orange color makes me believe this combo suits
my needs perfectly :) I also have Maimeri, Daniel Smith, and Winsor and
Newton pigments of similar colors.

I've got two tubes of "gamboge" M. Graham, and one is a different PY:
(151), so there has been a change in formluation, but I don't think the
yellow is as crucial as the magenta. I prefer transparent yellows.

When using these colors, I find that I use about a proportion of yellow in
my mix that errs closer to 1 1/4 to magenta 3/4...how I measure is I
overflow the yellow teaspoon and I underflow the magenta teaspoon in my mix.

Hence, my formula is, as I've said before here, a whole tube of the color
mixed in a 50ml plastic bottle of gum arabic 1+2 water (i mix from powder).
That is my stock. Then I take a tsp of this, more or less, and a tsp of gum
1+2, to 1 1/2 tsp water to 1/2 tsp of saturated am di. With diginegs I
expose the yellow a little shorter than the magenta, so yellow may be closer
to 4 mn and magenta 5, not that that is crucial, since a longer development
can also take care of that. That's it. Spray development, usually. Sized
paper.

Not that printing 10 or 11 layers is a bad thing; it gives a nice gloss to
the image, but **having** to do that is not necessary to get a tricolor
print. I have never felt a need to do over 4 or 5. But you say your print
looks beautiful so maybe you are doing the right thing?
Chris

From: "Carmen Lizardo" <carmenlizardo@yahoo.com>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Friday, October 29, 2004 8:44 PM
Subject: gum prints from digital color sepations. (Since the topic has been
brought up)

> Dear List,
>
> I've been trying to make gum prints from color
> separations done in Photoshop, but I only got a
> satisfactory print after 10 layers of colors. I
> started with a cyanotype as my first color and then
> used Smiincke ruby red and Grumbacher cadmium yellow
> light. After, I used Winsor ultramarine blue mixed
> with the Grumbacher cadmium yellow light, next I
> applied the ruby red again and fallow by several
> layers of Payne's gray and neutral tint (mixed
> interchangeably with blue and red). The print looks
> beautiful, although the colors don't match the
> original. But I was wondering if there is an easer way
> (less layers) of making a color separated gum print.
> Thanks!
> Carmen
>
>
>
>
> __________________________________
> Do you Yahoo!?
> Take Yahoo! Mail with you! Get it on your mobile phone.
> http://mobile.yahoo.com/maildemo
>
Received on Sat Oct 30 09:46:00 2004