> Please, could you tell me how you prepare the plexi or the white plastic to develop on it?
I clean it just with warm water and a mild detergent or household
cleaner.
> I mean does it sticks enough to print the image on it and not enough to allow the image to
> be transfered on paper afterward ?
Plexi and many other plastics just have the right surface that the
gelatin sticks only while wet or humid. After it has dried completely
(!) you can peel the gelatin/paper off, sometimes a knife is necessary
to slip between plexi and paper. If it doesn't want to leave the plexi
it still is too humid and must be dried more, e.g. with the help of a
fan or hair dryer.
This doesn't work with clean window glass!! You'll never get the paper
off without damaging the image. Waxing might help but I ddn't try it
because I found plexi much better - it won't break, for instance...
> I am interrested to print 4 colors Ultrastable on paper. Does it works too?
It should. I remember seeing on Charles Berger's Ultrastable homepage
that he recommends sanding down the plexi a bit. The adress was posted
some weeks ago, I think. Sanding down certainly helps and I did that
many years but now I found a new sheet of plexi just as good. Maybe it
depends a little on the material you use and how you clean it. The
waxing solution could certainly be applied to plexi, too, but until now
I found this additional trouble unnecessary.
BTW: When developing a carbon transfer on plexi, exposure time and
contrast can be judged by laying the (dry!!) plexi face down on a white
sheet of paper. By looking through the plexi you'll see the image as it
will look after framing. If s. th. is wrong, just clean the plexi and
try again..
Klaus Pollmeier