From: Sandy King (sanking@clemson.edu)
Date: 03/08/03-08:58:53 AM Z
Hi Scott,
Nothing stands out as inherently wrong about any of your procedures.
I would have suspected first the gum arabic but since you appear to
have already tested that proposition the problem may lie elsewhere.
Nonetheless I am inclined to believe that the splotchy look comes
from uneven application of the sensitizer, perhaps made more
difficult by the use of gum arabic.
You mention the density range of your lith negative, but not the
Dmin. That would tell me more about required exposure time than
density range. In kallitype you will typically see solarization in
the shadows and on the clear areas if the negative is very dense, or
very contrasty. What happens is that it takes so long to get
acceptable density in the highlights that the shadows are
overexposed, and they solarize. However, a DR of 1.6 is quite normal
and your exposures appear to be very short and I am surprised that
you would get solarization in this situation.
Something may be wrong with the silver nitrate, though the cloudy
condition you describe is not typical in my experience. When mixed
with distilled water I get a very clear 10% silver nitrate solution
within just a minute or so of mixing.
My suggestion is to make several changes at once and see what
happens. For example, try all four of the following together.
1. Try a paper other than Stonhenge.
2. Eliminate the gum arabic.
3. Develop in a 20% solution of ammonium citrate or sodium citrate
instead of sodium acetate, and use fresh solution.
4. Use another negative, preferably an in-camera negative with DR of
about 1.4 and a Dmin in the shadows of about 0.15-0.25.
If the print is still splotchy and solarized I would then suspect
either the silver nitrate or ferric oxalate solution.
Sandy
>Hi all,
>
>I'm having a bad night tyring to print kallitypes and thought
>someone could shed some light on what might have been going wrong.
>My prints seem to be solarizing in the shadow areas, coming out
>splotchy, and printing extreamly quick (2-3 minutes) under a bank of
>UV flourescents.
>
>I was trying to print a lith negative that has a density range of
>1.6 on gelatin sized Stonehenge paper (w/o hardener) using a 50/50
>mix of 20% ferric oxalate and 10% silver nitrate plus 4 drops of gum
>arabic (having sucessfully used previously).
>
>Thinking that the gum arabic might be the culprit, I sensitized and
>printed a sheet with out it and got the same results. I also tried
>mixing fresh silver nitrate as there was a slight cloudiness to it;
>no change. I mixed a stronger solution (15%) of silver nitrate and
>that helped slightly. The ferric oxalate appears fine (clear and
>light colored) and the addition of hydrogen peroxide didn't help.
>
>I am using sodium acetate for the developer (75g + 3g tartaric acid
>per liter). I didn't think the developer was causing my problems but
>I mixed a fresh batch anyway; no change.
>
>If anyone has any ideas I would be glad to here them. Maybe it just
>isn't my night to print.
>
>Scott Wainer
><mailto:smwbmp@starpower.net>smwbmp@starpower.net
>
>P.S.
>Reading "The New Platinum Print" I came across a paragraph saying
>that one could make potassium citrate by mixing potassium carbonate
>and citric acid but did not give quantities. Would anyone know how
>much of each I would need to make 1 liter?
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