Saturated solution of pot. dichromate
Liquid gum-arabic by Winsor & Newton (I know this stuff is extremely $$$ but
I had the bug to print RIGHT NOW and I couldn't find anything else.)
Winsor & Newton Lamp Black tube pigment
Fabriano Artistico watercolor paper
I figured I'd start out with Crawfords method so my solutions were combined
20ml Gum arabic
(thoroughly mixed with pestle)
20ml Pot Dichromate (25g:160ml distilled water)
I coated a number of sheets (all with different amounts of sensitizer) and
processed them all "automatically" in water around 75 degrees (room temp).
None of them even looked close to decent.