Imagesetter to print to B&W paper?

[switchedcraigmageephotogra]

After reading a few posts here and there about frontier and lightjet

printing on b&w paper, and remembering someone tell me about b&w

prints off a lambda on ilford multigrade, a little idea poped into my

slightly crazy brain. <p>

from what i remember the Lambda was basically developed from one of

dursts imagesetters, and as imagesetter output B&w films to be used

to make printing plates, why not see if it's possible to simply

substitute the film with b&w paper (RC would i'd imagine be easier to

handle)?!? hey presto a digitally created b&w print...<p>

Now that a lot of printers are going with straight-to-plate machines

maybe there's someone out there willing to try something different on

their old film imagesetter...<p>

am i just insane or would this be possible???

[scottfrey]

I've done it. Years ago ;)

 

The most practical way was to make a stocastic screen in photoshop (mode -> bitmap -> (using diffusion dither))

 

 

There was a fair abount of experimentation with what was the best resolution to start with (in the bitmap conversion, you must choose the imagesetters native resolution, i.e. 2400dpi for me), and it was essential to apply a tone adjustment prior to bitmap conversion to get somthing like the same gamma. To do that entailed making a guess, outputting a (10 step) grey scale, measuring on a desitomiter, lather - rinse - repeat. The end result was pretty decent, but we found it better to output the same file to a neg, and contact printing it to slightly blur the hard imagsetter dots (output wrong reading and contact through the base). We did this whole process to create rock-band promo photos for one of our staff. The amount of labor and material would make it cost-prohibitive as a commercial product. This was before lightjets of course, and people were quite impressed by the logo and type being incorporated into the photo.

 

You would need a processor also, Imagesetters take roll-fed material and you would have to use the proper chemestry, etc. I would guess a used 'setter and processer would set you back several thousand (and several hundred for materials and chemicals, it's not available in small quantities

[andy_piper2]

Craig: as Scott alludes to by mentioning a stochastic screen - imagesetters are designed for litho-type imaging, not continuous-tone grayscale. The laser that exposes the film is either on or off and images only black or white - no in-between grays.

 

So you'd have to come up with some way to represent the grays - either a halftone or stochastic (random-dot) screen, or a major software rewrite (and probably a new laser as well) to make the laser light variable in intensity (which is probably what Lambda did, more or less).

 

But nice creative thinking...!

[switchedcraigmageephotogra]

yeah cool....

I figured it would only be monotone, bit like something i read ages ago in a magazine about filling ink cartridges with liquid emulsion i think then printing onto fineart paper and processing (or it might of been dev printed onto photopaper thats just been exposed to light.)<p>

I have all sorts of crazy ideas at times, like i'm trying to get hold of an old inkjet to fill the cartridges with pantone floro inks from the trium pens so i can print floro colors... probably wont work but it's worth a try.