Re: Negatives from computer

Kouklis Kerik T (KOUKLIS_KERIK@aphub.aerojetpd.com)
20 Mar 96 14:56:20 PST

> > I have found negatives created via laserprinter on transparent material
> > to be not dense enough for Van Dyke, etc. I routinely run my files out on
> > imagesetter ("linotronic" et. al. usually avaialable at local commerical
> > offset printer), but you end up with a screen pattern, i.e. 120 dpi., etc.
>
> The trick here is to NOT use a line screen. Make a bitmapped file using
> the "Diffusion Dither" option (assuming you are using Photoshop). I
> would recomend a final output resolution no lower than 300 dpi. 600 dpi
> will still show significant improvement over 300 dpi.
>
> David Fokos

Yes, David is very correct. Diffusion Dithering in Photoshop is the
trick. Dan Burkholder has written a fine book giving a step-by-step
approach to making digital negatives using this method. His book
includes a disk that has Photoshop contrast curve files that adjust
the digital image to output negatives from an imagesetter that print
very well in platinum/palladium (the only medium I've tried these
negatives with so far.

The book is called "Making Digital Negatives for Contact Printing"
and is available from PhotoEye books in Santa Fe. Dan can be reached
via e-mail at BladedIris@AOL.COM

By the way, I just found this mailing list yesterday and am very
excited to become a part of it. I am a platinum printer shooting
mostly in the 7x17 and 8x10 formats and living in Placerville, CA.

-Kerik Kouklis