U of S | Mailing List Archive | alt-photo-process-l | Re: Stock Paint:Gum Solutions?

Re: Stock Paint:Gum Solutions?

OK this is it--one last email before I get on the road. Have to teach a gum workshop in Missoula MT 200 mi away and I have to have my hubby drive me there because I can't drive with a knee brace. He has to sit in a town for two days entertaining himself so you can imagine he's one happy camper.

I mix all pigments 15ml tube in a total volume of 60ml because that is the size nalgene bottles I have.

At time of use I cut my pigments with plain gum--thalo gets cut as much as 1+5, yellow maybe 1+2, magenta maybe 1+3, depending.

Stock solutions are a cinch to use, and I only have problems with the heavy pigments which settle and separate into a sludge on the bottom--nickel titanate, cerulean, cadmiums. Since I no longer use these colors, mixing stock is not a problem for me as far as separation is concerned.

I think your thalo may be too concentrated, but I notice a progression of yellow-magenta-thalo which I also do as far as strength.

One more thing--at time of use I may decide to do an undersaturated print, too, in which case I cut all pigments way more.

There are several list members who have this down to a real exactitude--Marek, Dave Rose used to, and they'll tell you exactly how much. OH, you could do a search for Dave Rose's posts a few years back but he did use powdered pigment.

Christina Z. Anderson
----- Original Message ----- From: "Loris Medici" <mail@loris.medici.name>
To: <alt-photo-process-l@usask.ca>
Sent: Wednesday, October 22, 2008 7:56 AM
Subject: Stock Paint:Gum Solutions?

I was reading handprint.com's "The Secret of Glowing Color" page, which
contains very good and interesting information, especially in the section
"Not Black, Not Light".

I slowly feel the need of making stock paint:gum solutions, in order to
get more consistency and ease of use. Mixing small amounts of paint:gum
solutions is hard to do consistently, especially with strong colorants and
small image sizes. (Because squeezing small amnt. from the tube is not

I decided to make stock solutions as listed below:

Yellow  PY151  1:2 (1:4 final) -> 15ml paint + 30ml gum
Magenta PV19   1:3 (1:6 final) -> 15ml paint + 45ml gum
Cyan    PB15:3 1:4 (1:8 final) -> 15ml paint + 60ml gum

Since the stock paint:gum is further diluted 1:1 with dichromate, the
actual paint dilution in the coating solution will be exactly the half of
what it is in the paint:gum solution. (See inside parenthesis.)

This question goes to users of stock paint:gum solutions (such as
Katharine and Christina):

Do you find above figures close to ideal? What is your experience with
those pigments? Anything to pay attention / be careful about using
paint:gum stock solutions?

Thanks in advance,