Diffusion with contact printing

greenspun.com : LUSENET : Large format photography : One Thread

I would like to do some work with diffusion in the darkroom. The problem is that right now I am only working with contact prints. Most of the prints are 5"x7". The diffusion that I have done in the past has been a partial diffusion for about half of the exposure. My guess is that any diffusion done between the light source and the negative in a contact prosess will not show up. I might also add that at the present time I am using a diffusion enlarger as my light source. I am also looking into a different light source. The main requirement for a light source is the ability to use contrast filters. Any one out there have any ideas?

-- Bruce E. Rathbun (brath@iquest.net), September 18, 2001

Answers

try using some frosted acetate or nonglare glass between the neg and paper.

-- rich silha (rsilha@visi.com), September 18, 2001.

Tissue paper.

-- Chad Jarvis (cjarvis@nas.edu), September 18, 2001.

I would think that anything that seperates the neg slightly from the paper would work. That could be anything from thin glass to Saran Wrap. The ideas from the other posters should also work, but I think I would try seperating the neg and paper first.

Regards,

-- Doug Paramore (dougmary@alaweb.com), September 18, 2001.


Vellum from a graphic-arts place works pretty well, I've found, for diffusion at the printing stage, either between the negative and paper when contact printing or on top of the printing paper when enlarging.

-- David Munson (orthoptera@juno.com), September 19, 2001.

If the idea is to use VC filters to adjust the paper contrast; then why not just stick the filters in the neg carrier or filter drawer of the enlarger? If it's marks on the filters that concerns you, then just throw them out of focus with the enlarger lens, or fit the filters below the lens.
As you guess, the diffuseness of the light-source has little effect on the character of a contact print, except to even up the lighting.

-- Pete Andrews (p.l.andrews@bham.ac.uk), September 19, 2001.


Moderation questions? read the FAQ