RE:Gum printing ?

After viewing Sam's Tri-color gum over cyanotype prints last summer and
reading the recent article on the unblinking eye. I have started to try to
learn the process and am making progress. First a special thanks to
Katharine for her informative web page which has given me a wealth of
information. Sam for his work and article and Christine for description and
prints currently on the unblinking Eye. I better give Ed some praise for his
website and contribution to this community of alternate process.

I am making digital 8x10 negatives which print in platinum/palladium between
2minutes to three. Three coats of gum 1 1/2 minutes to 2minutes, six coats
gun 1 minute each coat. I am mixing 5cm gum to 5cm potassium dichromate with
1 gram of water color pigment. I am using Daniel Smith: Antraquinoid Red,
Cadmium medium yellow and Windsor & Newton French Ultramarine. The red and
Yellow seem to work well and l looking for a better blue.

One of the things which I am unsure about is the order of the layers to make
a color print. When I use blue for the first coat I am able to register my
negative with out trouble. When I use yellow for the first layer it is much
harder to see the negative come into registration, but I achieved the best
color by using Y, M then B negatives.

I am unsure how to fine tune the color balance. More time for one color or
more pigment? Since I am using Red, Yellow and Blue to make a color print
would this be the same as traditional silver additive color printing.

I will scan several prints and post them to phto.net so that you may have a
better idea how to give me direction. The nude negatives where on (cheap
transparency film which ran during exposure)
http://www.photo.net/photodb/photo?photo_id=2269073

http://www.photo.net/photodb/photo?photo_id=2269086
Best Regards,
Robert Cockrell

  
Received on Wed Apr 7 15:10:59 2004