>You asked:- Are they still doing alt processes at the Art School in
Gloucester for it was there that I discovered Gloy when there was no gum
'to be had not even for ready money'.
My apologies for my tardy response, but being self employed I either get
too much work or no work at all, and for the past few weeks the former
rare state has prevailed. Coupled with which, my original reply could
not be delivered, or it was sent to Alpha Centauri. Demon are not quite
clear on that point, so I am trying again!
They no longer do alt processes at Gloucester or Cheltenham for that
matter. I belong to an amateur group of monochrome enthusiasts called
'The Cotswold Monochrome Fine Print Group', and I have managed to get
one or two members interested in Bromoil, Carbon printing, and Gum
bichromate. I should add that we are all beginners where alt processes
are concerned.
I have ordered a small quantity of the deionised ossein 260 bloom,but
meanwhile I have been trying out a gelatin scrounged from the laboratory
of a friend. This gelatin is of French manufacture (Duche'), is a fine
powder and is labelled '800B', and that is all the information I have.
Helped by your suggestions I have managed to obtain some results with
the oil printing, using this gelatin. I blended it with 25% of SUPERCOOK
food gelatine from ASDA, and added chrome alum in the quantity you
suggested.
I don't know if the addition of the SUPERCOOK is necessary, but I
assumed that the 800B gelatine would be quite hard as it was originally
obtained for testing in an experimental commercial imaging process. I
thus reasoned that the addition of a soft gelatin would improve the
water absorbtion in the highlight and mid tone areas of the exposed
print.
I sensitised the coatings with 5% ammonium dichromate in 60/40 water/
alcohol, applied by a paint pad. After exposure and washing I cleared
the dichromate stain with 5% sulphuric acid, after further washing I
dried the prints for four days before inking.
I have not tried immersing the coating in the dichromate, simply because
of the problem of handling large quantities of ammonium or potassium
dichromate solutions in a confined space. I would, however, be grateful
for the groups views on the advantages of immersion over brush or pad
application.
Also re: gum bichromates. Has anyone any experience of using poly vinyl
alcohol as a substitute for gum arabic? If this has been discussed
before I apologise.
Alex.
Alex Nanson
Gloucester UK