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brighamr
5-Apr-2015, 00:27
hi

I have been enjoying doing some liquid light dry plates and guess that I could try reversal processing them or contact print them onto another glass plate but what I'd really like is a direct positive dry plate

does anybody know if this is actually possible or is the coating of direct positive a different thing

it is interesting that Slavich seem to be about to release direct positive paper so maybe they will sell tubs of the stuff as well !

robin

jnantz
5-Apr-2015, 17:47
hi robin

http://www.largeformatphotography.info/forum/showthread.php?120607-Paper-neg-positive&p=1227168#post1227168

this thread has instructions on how to do this with regular photo paper
i do not think it would be difficult to do it with glass plates ( make sure your emulsion is hardened )
that said, it might be easier to project / contact print negatives or paper negatives onto the plate
much easier than reversing an image, but not as much fun ;)
i spent a couple of years printing on glass instead of paper, it was a lot of fun, and no reversal chemistry needed !

good luck !
john

JoeV
10-Apr-2015, 11:58
I'm curious to know if coating the dry-type emulsion on a black substrate will produce an effect similar to tintype or ambrotype. I've briefly experimented with lithography film superimposed against a black background, and at certain viewing angles I can see a reversed (i.e. positive) image. I suspect that, in order to accentuate the effect, a developer and/or fixer combination has to be used that makes the fixed silver emulsion more highly reflective, thus accentuating the faux-positive effect.

I'd like to see someone like Ilford coat their paper emulsion on black RC paper, then offer the corresponding developer and fixer to accentuate the positive image, in place of Harman's now discontinued Direct Positive paper.

~Joe