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>
> Sandy,
>
> I've have no personal experience with Mylar but your note brought to
> mind some published information that might be of help. An old TAB
> book titled "How To Make Old-Time Photos" by John McDonald and Melba
> Smith Cole discusses a wet carbon method in Chapter 4 which utilizes
> Mylar. I believe there is an expired patent on this process, if I
> have a little time I'll try to dig this out for you. Good luck
>
> Art Chakalis
> Columbus, Ohio, USA
This sounds like the process shown to me years ago by Darryl Jones,
which was a technique to avoid humidity problems by exposing carbon
tissue while it was still wet. The mylar was used to isolate the
negative from the still damp tissue. (didn't always work :-(
I've adhered both gravure resist (from Autotype) and carbon tissue
(from where ever Dr. Green got it) to mylar with no problems. It is
a useful way to proof exposures and to make density readings (hard
to read the transmission density through a copper plate). Once
dry, I found the adhesion of the pigment/gelatin to the mylar to
be tenacious. I can't do anything but speculate as to Sandy's
problem. Possibly it is the way he prepares his tissue, or possibly
it is something that is added to the Light Impressions mylar he is
using. I do know that the mylar I was using wasn't frosted or prepared
in any special way.
Hope this helps,
Carson Graves
carson@ileaf.com