Michael Desjarlais (mpdesja@swcp.com)
Sun, 21 Feb 1999 13:05:36 -0700
Chris,
If you continue to have problems and you determine that the problem is
indeed with your cold light head, you might decide to try a relatively
simple fix before spending money on a new enlarger. A few years back I
had a similar problem with a Zone VI cold light head and fixed the
problem by projecting the cold light image to size (i.e. 1:1) on a sheet
of high contrast film and then developed it to give what I called a
contrast mask for the cold light head. The negative, after processing,
is inserted into the cold light head in the proper orientation to smooth
out the uneveness in tone. Unlike your experience, I also saw problems
in the prints. E-mail me off list if you would like my notes on how to
do this. Others have tried this trick with good success.
-Mike Desjarlais
Chris Stone wrote:
>
> I'm having a curious bit of difficulty and I'm hoping someone can
> suggest a solution--or at least give an explanation. I'm trying to
> enlarge a 4x5 negative to 8x10, going from negative to interpositive
> to enlarged negative. For some reason the light tubes in the variable
> contrast head are projecting very pronounced stripes on the lith
> negative. (I'm using full green for exposure.) I'm puzzled by this.
> There's a diffusion plate on the Aristo head, and I've never noticed
> this when making prints. The negative I'm trying to enlarge is fairly
> thin and also developed in D-23 rather than pyro, so perhaps this is
> significant? Any insights into what's going on would be much
> appreciated.
> -- Matthew
This archive was generated by hypermail 2.0b3 on Sat Nov 06 1999 - 10:06:53