Re: Exposure - illuminating spectrum

From: Walt (wgoettman@mm.wyeth.com)
Date: Wed Dec 08 1999 - 10:27:41 /etc/localtime


> But this would still not answer my interest. I am not just interested
> in how fast an exposure can be made. I am interested in what result in
> the print can be produced (or controlled) by a certain spectral
> illumination. Is there any quantification of variations in contrast as
> Sandy King mentioned for some processes? What other qualities are
> influenced by a shift in spectrum?
>
> Various light sources and window material have been discussed for quite
> a while. Has anyone, or is anyone investigating what differences may
> occur in the print as the exposing spectrum is altered?
>

I found it interesting that Cartwright Mills notes in an Autotype
publication circa 1930s "Notes on the Rotary Photogravure Process" that
a 5% dichromate solution is flatter than a 3% solution mainly because
the additional dichromate acts as a yellow filter.

Walt



This archive was generated by hypermail 2b29 : Tue Jan 11 2000 - 12:10:48