>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..
We have used Cobex, a white opaque plexi, for many years to achieve what
Klaus is talking about, it's great. Especially when working with 3CC.
Another BTW: Even if Luis or Sandy don't believe it or can explain it;)
With 3CC it's necessary to clear the prints developed on plexi, we have
noticed the difference.
Hans&Chia