From: Jack Fulton (jfulton@itsa.ucsf.edu)
Date: 05/11/00-06:26:10 PM Z
Ferrotype or glaze
Gee, here is another 'old' process returning to life.
The newspaper and publishing jargon always cried for, "Gimme an 8x10 glossy!"
Theoretically, the glaze, or gloss, added to the photographic surface gave a
greater dimension and those who copied them for reproduction in
magazines/papers preferred a 'glossy' print to one that is flat.
There are two methods: hot and cold.
Hot mostly uses a piece of chrome plated steel or highly polished stainless
steel.
Cold can also be done using a smooth glass surface.
Cold is more problematic than hot due to it being slow. First degrease the
glass surface. Washing w/dilute ammonia would work. i'd then use a window
cleaner such as Cinch or Windex to again clean it. Used cloth baby diapers
are excellent rags for this as they are pure cotton.
Don't harden the emulsion because it is the 'soft' emulsion, adhered firmly
to the surface, that allows the glaze to occur.
When cold glazing, squeegee your wet glossy paper (do not used matte or semi
matte) face down on the glass surface (or metal) and back up with a couple of
1/4" (5 cms) of felt pads. It would even be handy to have a thin layer of
silica gel even layered in a plastic bag, dried, between the two layers of
felt to aid is pulling moisture from the print. The prints, under normal
ambient room temperature and humidity, ought to be dry in 60-90 minutes.
Hot glazing normally is done w/a print dryer. Sometimes these can be found @
thrift stores or can still be purchased new at a reasonable cost. They are
primary a curved surface w/a heating element inside and a cloth cover which
"locks" the print placed on the chromed metal surface to the dryer. These
prints dry very fast. By rubbing your hand over the cloth surface, you can
tell if the print is dry and then remove the print from the dryer and it
should 'pop' off the plate.
Always clean the plate after each use.
If there are problems with the glazing and spots occur, it could be due to:
1. fix remaining due to poor washing
2. dirty plate
3. hard water
sometimes, with he latter, a bit of photo flow or glycerin (I think Edwal
might make a glazing liquid still) can aid, but don't make the concentration
too strong.
Do not try glazing RC papers!
Jack Fulton
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