Re: Luminosity

Luis Nadeau (nadeaul@nbnet.nb.ca)
Fri, 06 Jun 1997 00:58:40 -0300

At 5:57 PM -0300 97/06/05, Dwight Shackelford wrote:
>I got some slides back today, and was looking at doing some combinations
>of slides to form one image. What struck me though, was how important
>the element of luminosity was in the images I was getting.
>
>Given that, I'm looking for a way to help duplicate in a print the
>luminosity and lushness of color that I get with slides.

You won't get it. A reflection copy (print) can't give you the range you
can obtain from a transparency. This said, prints add texture and reflected
light you can't get from a slide.

>I'm still the newbie here, so this might be a dumb question, but I was
>wondering if gum bichromate would do that with many layerings, or
>whether working with a translucent or transparent substrate would
>accomplish the trick (glass or plexiglas, etched so it has some
>"tooth"). Sort of duplicating for color what the Woodburytype did for
>greyscale with its depth of gelatin (I've not only mixed my processes
>here, but probably my metaphors too, but I'm having a hard time
>describing what I'm wanting. I'm thinking depth of gelatin would allow
>something more than just reflecting off the surface).

Most, if not all woodburytypes you saw were varnished. The carbon transfer
process -not for beginners- is superior to the woodburytype in many ways.
Since multi-pigmented layers are possible in carbon one could also add a
*non-pigmented* gelatin layer where the gelatin would be applied
proportionally to the amount of light that was allowed through the
negative. This is a secret however, so don't tell anyone...

Here's another one: To a finished print, you could add a coat of
dichromated gelatin (or gum), *sans* pigment and once dry, expose the print
to strong light through the back. Develop the unexposed gelatin in hot
water (40C) or the gum in room temperature water. Areas of the print that
were not protected by the dense pigment will retain the colloid for a
different effect.

Luis Nadeau
NADEAUL@NBNET.NB.CA
Fredericton, New Brunswick, Canada
http://www3.nbnet.nb.ca/nadeaul/
http://www.primenet.com/~dbarto/lnadeau.html