I have been working with Imagon (Riston) film for Howard process
intaglio-type prints for about a year. If you're looking for "imitation"
photogravure, you may not like the "intaglio-types" - the prints have a
different look - they are shorter in tonal range and lower in resolution
than photogravures. I have come to love the intaglio-type process, but not
everyone does.
The process is relatively easy: a plate with Riston film laminated to its
surface is exposed to a halftone positive under strong UV light (I use
mercury vapor - "black-lites" apparently do not work well). The exposed
plate is developed in a simple solution of washing soda (sodium carbonate)
and water for a few minutes, squeeged off and dried. At this point, you can
either ink the plate pull 10-25 prints (non-etched Intaglio-type) or etch
in acid (ferric chloride but nastier mordants will work OK) for a larger
edition and the ability to work back into the plate.
I prefer the non-etched Intaglio-type process - it is quick, much more
forgiving has a slightly longer tonal range. And no acid at all !
The process is fairly foolproof, but there are many tricks to getting good
results. I would strongly suggest taking a workshop: see Fairview College's
web page for summer workshops in Alberta:
www.mtsu.edu/~art/printmaking/workshops.html#keith.
Good luck.
Felicia Lovelett