New dneg process - no interneg required

[keithwms]

Similar to an inkjet printer, the paper would be exposed with a head containg tiny LEDs or something similar. The printer would be driven by a computer and output would come directly from Photoshop or similar image editor. That would eliminate the problem and expense of ink.

Anyway we can dream.

Don, isn't what you describe a lightjet, basically? But I think they only use RA4 paper and there's no true matte, so yeah, it'd be nice to be able to work with silver paper in its various forms, without using ink... but really, the ink is no big deal. I think if I can find some more water-soluble inks then it'll really be trivial.

I can imagine equipping an inkjet with fiber-coupled LEDs to expose b&w paper, that part is the kind of weekend tinkering I enjoy. But the software to generate continous tone exposures, that is something I wouldn't care to think about!

 

[E Thomson]

For DIY, you could experiment with air-brushing a water-soluble layer of gelatin or gum onto the photographic paper. Then any ink-jet could be used and the printed negative image would clear with water as a first step. Gelatin could be used, but it gels when cool and can be difficult to spray, so I would experiment with gum arabic, carboxymethylcellulose or polyvinyl alcohol.

As a mechanized process, it seems it might be fairly trivial to deposit a thin water-soluble film over photographic paper to make it universally ink-jet compatible.

 

[keithwms]

As a mechanized process, it seems it might be fairly trivial to deposit a thin water-soluble film over photographic paper to make it universally ink-jet compatible.

Indeed. I am thinking krylon but water soluble. The only thing is, I know a lot of things that are UV transmissive (nice for any alt process) but not water soluble. There must be a billion arts & crafts sprays, I guess I just need to try some things.

 

[Jordan]

Keith -- really interesting process! What I'm most interested in knowing is how good your D-min is... how "clear" can you get the highlights? Are they paper-white, or a very light gray?

 

[keithwms]

Keith -- really interesting process! What I'm most interested in knowing is how good your D-min is... how "clear" can you get the highlights? Are they paper-white, or a very light gray?

Thanks. Hard to tell without doing a careful test, with a real mask in place during exposure so that I can really have an area that should be paper white as a comparison. If I do that then I can scan it and make some quantitative comments.

A least I can say by casual inspection that the highlights are very close to paper white. But it depends on how good a job I do clearing the ink. In that first example I did a lousy job. In the second I was getting better at it. What I found is that you want to run the paper through the printer, expose it ASAP, then dunk it in water ASAP. The quicker you do all that, the easier the ink will come off. If you do it all within a minute or two, which is actually pretty easy, then the ink comes off like magic.

Obviously a proper solvent for the ink, or a water-soluble ink would be a nice innovation; I tried various things like rubbing alcohol and acetone but those didn't seem to help much, once the ink has dried. I am still thinking that bleach may be the cure-all and might work equally well on fiber.

I'll do some more tests when I have time.

 

[Jordan]

Actually -- I wasn't thinking necessarily about how easy it is to wash the ink away (I think you and the ink manufacturers are working at cross purposes here!) but rather what the light-blocking ability of a "single coat" of ink is -- is the enlarger light able to fog your paper through a solid patch of black ink?

 

[keithwms]

Ah, okay. Qualitatively, it looks light the matte black ink has enough opacity to do the job. I'm not using a fancy inkset or QTR or anything like that this point, just a single matte black ink. So there is room for improvement but the early result is already quite good.

 

[Ben Altman]

Obviously a proper solvent for the ink, or a water-soluble ink would be a nice innovation; I tried various things like rubbing alcohol and acetone but those didn't seem to help much, once the ink has dried. I am still thinking that bleach may be the cure-all and might work equally well on fiber.

You might try MIS Base or similar third party cleaner/dilution agent. I'd use a mask, though, who knows what's in that stuff...

http://www.inksupply.com/product-details.cfm/p/2614.html

 

[codex0]

What I would like to see instead is a digital exposure unit that could be used in the darkroom with gelatin silver paper. Similar to an inkjet printer, the paper would be exposed with a head containg tiny LEDs or something similar. The printer would be driven by a computer and output would come directly from Photoshop or similar image editor. That would eliminate the problem and expense of ink.

One of the grad students and I have been kicking the idea around of modifying a film recorder to do just that - putting an enlarging lens and a shutter on it, making it into a high-resolution, digital projection enlarger. I have several film recorders, but unfortunately don't have any of the driving software to try it...