>.... When you speak of glazed ceramics, I assume you are talking
> of images "exposed" onto them, not glazed ceramics in general, or images
> glazed onto the piece. I would be interested in hearing more about
> "alt" images on glazed ceramics, processes, considerations, etc.
>
As far as I know the luminosity of photos on ceramics is more or less
comparable to the luminosity of the same clay & glaze with no photo. ( The
cyanotype on ceramics I've seen, fired or unfired, was dead mat and drab.)
I don't know about projecting an image onto ceramics, although perhaps Art
Chakalis's souped up enlarger (among others) might. What comes to (my)
mind are dust-on process -- add honey or sugar to a dichromate emulsion so
the underexposed parts remain sticky & dust the colorant onto it; make or
have made a photo decal which you apply to the clay at one of several
possible stages; and carbon transfer. I imagine there are others -- there
are photographers on the list who do photo ceramics who could tell more.
However I expect relative luminosity depends on the clay, the glaze, the
firing temperature, and a bunch of other variables, not just the
particular method.
Judy