U of S | Mailing List Archive | alt-photo-process-l | Re: gum mixes

Re: gum mixes

  • To: alt-photo-process-l@usask.ca
  • Subject: Re: gum mixes
  • From: "Christina Z. Anderson" <zphoto@montana.net>
  • Date: Thu, 03 Jan 2008 07:23:24 -0700
  • Comments: "alt-photo-process mailing list"
  • List-id: alt-photo-process mailing list <alt-photo-process-l@sask.usask.ca>
  • References: <C3953B52.BBED%henry.rattle@ntlworld.com><001d01c84641$f0c8f720$a15dc844@christinsh8zpi><25E8FFA1-0647-4E94-A4F0-3A22FABA65CF@zeelandnet.nl>
  • Reply-to: alt-photo-process-l@usask.ca

Dear all,
So this is what I have so far--only 10 gum printers on the list apparently :)
The range of practice of gum never ceases to amaze me. In historical times it was 10% gum to 100% gum (the latter was mixed 1 gum powder to 1 water--I know, it is not technically a 100% solution but that was what they termed it in those days--in other words, a 40% solution was 40g gum PLUS 100ml water, not in a total combined volume of 100ml.
Some questions: Marek, do you use dry am di at time of use? Henry and David, at time of use you mix essentially a half strength potassium dichromate and am I correct with your 1 di: 1 water: 10 (!) gum? How long are your exposures and are they in the sun? Guido, same thing--do you use that little potassium dichromate in your mix--essentially 1-5 parts gum to only 1/2 part pot di? If I have anyone's info wrong, let me know.
1.. Sam Wang 1+2 powdered and at time of use 1:1 with dry am di
2.. John Brewer 3+10 powdered, preserved with 15ml formalin per liter, at time of use 1:1 mix, changing this ratio for highlights and shadows
3.. Kees Brandenburg 3+10 LUMP which he says is 14 baume and at time of use 1:1
4.. Marek Matusz premixed gum, stock pigment mixes of 1 tube pigment in 120ml gum and at time of use 3pt gum/pigment to 3 pt water to 1 part AMT
5.. Joe Smigiel is premixed 14 baume and at time of use 1:1 pot di, tube pigments, sometimes powder pigments, sometimes mica or interference pigments
6.. Bill Mull is premixed gum and stock pigment made with gouache at 6 gum: 1 gouache and at time of use 1:1 pot di and one coat gums made with paper negs
7.. Hamish premixed gum and stock pigment solutions and at time of use 1:1, but sometimes 1:2
8.. Henry Rattle 70 to 200 Kordofan No. 1 LUMPS with few drops formalin and at time of use 1 di: 1 water: 10 gum
9.. Guido Ceuppens 200g to 850 water with 5gr sodium benzoate with stock pigments of 1 g watercolor tube: 6ml gum and at time of use 1 part stock:0-4 parts gum:0.5 pot di
10.. David Hatton 500g + 1 liter with 10 drops 100% thymol and at time of use 1 pot di:1 water:10ml gum with varying amounts of pigment depending on layer, color
Christina Z. Anderson
Assistant Professor
Photo Option Coordinator
Montana State University
Box 173350
Bozeman, MT 59717