Kevin O'Brien (kob@paradise.net.nz)
Sun, 21 Feb 1999 18:25:38 +1300
-----Original Message-----
From: FotoDave@aol.com >Lith film can be successfully processed for low
contrast, but to use it in
>direct reversal process is more difficult / challenging. The reason is if
we
>process the film to low contrast, the high density area is not fully
>developed, so after the reversal, the Dmin would be high, which will give
long
>printing time.
I had to use it as I couldn't get anything else and I was able to scrounge
some supplies from the local photo-litho coy. I reinforced the Dmin
sometimes by sandwiching more than neg together and got the density right by
eyeball. However the individual films would'nt have won prizes in a fine
grain contest; you could almost see the clumps at times.
Sufficient experimentation showed that it is possible to get a wide range of
positives with reversal processing and at least a couple of different trials
each yielded good printable positive intermediates (but poor slides). With
the right film it should have been possible to enlarge onto them for a
suitable negative by exposing fully for the darks on the easel and
developing to gamma infinity in Dektol or similar. (Other development
processes may be more suitable but a few quick trials should tell). The
negative would have looked thick, overexposed and contrasty. Also the
definition is more likely to have been preserved.
Kevin O'Brien
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