David,
I have for some time been using Agfa's CS film which, I think, must be
characterized as a lith film; in any case, it easily produces very
contrasty positives (or negatives) Agfa's G5c developer. It has surprised
me that the film apparently reproduces all intermediate tones quite
faithfully (with proper development, and possibly an initial water bath),
and that I can discern no 'lith effect'. Compared to Agfa's N31p the CS
film has a much straighter characteristic near threshold; this means that
where you would have to place your positive (or negative) somewhat up on
the N31p curve (to avoid the reduced contrast near threshold), the CS film
can be exposed right down to threshold. This, of course, again means that
you can use shorter exposures for your alt-photo process.
The only disadvantage of the CS film that I can think of is that
development is quite critical, and just a bit difficult to control.
Consequently I usually expose a couple of CS sheets and develop them
slightly differently, so that I can later select the best one.
One further advantage of the CS film is its price, costing only slightly
more than one-third of N31p.
Finally: I have been using the CS film only for the making of positives for
the polymer photogravure process, - but I can see absolutely no reason why
one should not obtain the same good results for negatives.
Strange Ross
Hvidehusvej 35
DK-3450 Alleroed
Denmark Phone: (+45) 48 17 42 92 http://axp.psl.ku.dk/~ross/