Hi - so I've played around with cyanotype, kallitype, salt, albumen and van-dyke - I can get reasonably good images out of those processes but just can't get anything from gum. I haven't tried it for 18 months having given up on it but thought I'd try again today. So I mixed fresh solution of 10% potassium dichromate solution, and then used:
- 2.5 ml of the fresh potassium dichromate solution
- 2.5 ml of gum solution 14 baume (from Wet Plate Supplies UK)
- 1cm of water colour paint
Mixed that up and coated on top of a dried cyanotype - once dried exposed under my uv lamp (600 watt grow lamp) - I tried a range of exposures from 1 min to 35 min and get the usual result of no image - well the half hour one had the slightest hint of an image. For comparison 5 mins is my usual exposure for cyanotype.
Washing in water then, as you'd expect, produces nothing - the gum emulsion easily rubs off if you then move across it with a paint brush - now I guess that's a separate sizing issue ( ? ) - do you have to size the paper after you've previously developed out a cyanotype ?
Any suggestions greatly appreciated.
- 2.5 ml of the fresh potassium dichromate solution
- 2.5 ml of gum solution 14 baume (from Wet Plate Supplies UK)
- 1cm of water colour paint
Mixed that up and coated on top of a dried cyanotype - once dried exposed under my uv lamp (600 watt grow lamp) - I tried a range of exposures from 1 min to 35 min and get the usual result of no image - well the half hour one had the slightest hint of an image. For comparison 5 mins is my usual exposure for cyanotype.
Washing in water then, as you'd expect, produces nothing - the gum emulsion easily rubs off if you then move across it with a paint brush - now I guess that's a separate sizing issue ( ? ) - do you have to size the paper after you've previously developed out a cyanotype ?
Any suggestions greatly appreciated.
I'll try again tomorrow and wang up the exposure and see where that gets me.
