Cor Breukel (cor@ruly46.medfac.leidenuniv.nl)
Wed, 06 Oct 1999 11:01:56 +0200 (MET DST)
Bromide drag?
This is a slightly off-topic question concerning processing of lith film
for continuous in-camera negatives.
I have used the LC1 developer, formulated by Dave Soemarko in PF #2 (a low
on metol and HQ developer, high on sulphite, using acidic bisulphite to
tame the lith film) and adapted it for in-camera negatives. I have used
Freestyles APH lith film. My tests resulted in quite nice continuous tone
negatives (at the expensive of film speed, I use 1 or 1.5 ASA...), when I
used the following ratios: (A:B:water) 2:3:5
Which is per litre (end concentrations):
0.6 gr. Metol
12 gr sodium sulphite
0.6 gr. Hydroxyquinone
3 gr. sodium bisulphite
I used a JOBO processor with a print drum with special plastic inserts;
these inserts make it possible for the developer to "reach" the back of
the film, they also cause a lot of turbulence judging from the foam on top
of the discarded solutions. For 2 sheets of 18 * 24 cm (7*9.5 inch) I use
500ml of developer.
The first series of negatives were quite promising, and printed nicely as
silver gelatine contacts when using a grade O filter, they also printed ok
as Kallitypes, but they could use some extra contrast/density (which isn't
really a problem with Lith film..;-)..).
My problem arouse when I made a further series: a couple of images with a
lot of clear empty skies with flagpoles, a lamppost etc. All these objects
exhibited a "smear"going up into the sky; a smear of added density on the
negative; lighter when printed. I vaguely remember something about bromide
drag; but I do not know what this exactly is.
How is this caused, how do you recognize it, and how can I avoid it? I
also thought this has something to do with exhaustion of the developer
(not unlikely maybe), but why is this only happening on places where dark
objects are next to light objects. I mean the JOBO is continuously mixing
the developer.
Any feedback appreciated
Cor Breukel
http://ruly70.medfac.leidenuniv.nl/~cor/cor.html
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