On 2007-10-21, Richard Knoppow wrote:

"piterengel" wrote in message
ps.com...
Hi, becaise it no more possible to find lith film I need
to try with a
qute common film to obtain very high contrasted pictures.
I have Efke
KB 25 and Rollei PAN 25 at home. Can anybody suggest a
developer to
have extremely contrasted subjects?
Thanks all
P.


The highest contrast is gotten using a lithographic
developer like Kodak D-85 which produces "infective"
development. However, D-85, and similar developers, use
Formaldehyde, which is nasty stuff.

I use Kodak litho film (not much) and one of their litho developers.
It does not contain liquid formaldehyde, but paraformaldehyte that
is a related compound. J.T.Baker have this to say about it:

http://www.jtbaker.com/msds/englishhtml/p0154.htm

As far as I can tell, I have never had any trouble with the mixed
working strength developer.

There are somewhat lower
contrast developers, like Kodak D-8, using Hydroxide, which
produce very high contrast but not quite what a true
lithographic developer gives. I don't think a lith developer
is needed unless you are doing true line work.
Lith film is still made but I don't know where to get it
outside of the US.
For pictorial purposes a print developer like Dektol
will give you quite a bit higher contrast on film than the
usual film developers but at the cost of being quite grainy.
Since print developers are cheap and easy to obtain I would
try one first to see if the contrast is high enough.




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