the print. The paper automatically feeds through the processor and
exits fully processed. When the print exits the processor, leave it
under the clear print exit cover for at least 15 seconds which allows
for complete drying.
Figure 211. Viewer and processing station
(b) To make a halftone print from a continuous tone photo or
drawing, you must use a halftone screen, dots up with the photo paper on
top (emulsion side down), between the split platen and copyboard, and
adjust the fstop and film exposure time to manufacturer's
recommendations. A halftone screen reproduces a continuous tone
photograph or drawing by translating the tone image (dot pattern) into a
line image. You find different quality halftone screens used in the
different printing systems. The more detail required of the finished
print, the finer the lines of the halftone screen. Once you have placed
the screen, you continue the copy process as before.
The Thermofax Machine.
You can use this process as an alternative to the diazo process to
produce viewgraphs. Although this process does not produce the same
quality viewgraph as the diazo process, its main advantage is
flexibility. You can produce viewgraphs using almost any printed
material. This process also produces spirit masters, gummed labels,
laminates, and paper copies. The film for this process comes in a
variety of colors and preframed (frame attached) or plain film.