Re:Contact Printing frames
Paul and Judith Simon (70760.1511@compuserve.com)
18 Jan 96 16:15:06 EST
The contact difficulty with large printing frames is likely due to the bowing of
the glass, not the force of contact around the edge. The more pressure that is
exerted by the back, the more bowing there is of the glass. There are two ways
of reducing this:
1. Use thicker glass. The deformation of the glass (bowing) as I recall is
proportional to the square of the thickness.
2. Use a spacer around the sensitized material and negative so that the
thickness of material in the frame is as close to unform as possible. If it is
thicker <just> inside the visible area of the glass it will press like a ring
and push the glass away from the center.
Paul Simon