Materials: Saturated pot dichromate solution- 1 year old, stored in dark place
in brown glass bottle. 'Gloy' gum - described by manufacturers (Henkel) as gum
adhesive suitable for card and paper applications - also 1 year old. Winsor and
Newton 'Cotman' water colour paper. Winsor and Newton water colour paints.
I first size the paper and dry it - usually with a hot hair dryer. Then, under
weak tungsten light, I make just enough emulsion for immediate use, by mixing
equal volumes of dichromate and gum with varying quantities of water colour
paint and apply it to the paper with a paint brush. I have been drying this in
a dark room by placing it in a empty developing dish on a warm dishwarmer. It
seems from what has already been written that this is probably not a good idea!
I then expose the paper through a negative to a uv sunlamp. Previously
exposures between 30 seconds and 3 minutes worked. They don't now! I then
'develop' the image in warm water by gentle brushing with a paint brush.
Does sunlight give better results? Problem is that sunlight is not reliably
avaliable here! What about negative quality ie does the process work better with
high or low contrast negative? Are there better materials I could be using?
Thanks again for your help