Using a LCD/LED screen as light source for contact printing?

[DannL]

I was curious if anyone was using a LCD/LED computer screen as light source for contact printing? And at the next level had anyone pursued projecting a digital/graphic mask via such a light source to facilitate what would normally be considered the traditional dodging and burning steps?

Cheers! O.F.

[DannL]

I'm sure the question posted above went over like a lead balloon. Here's are a couple images of what I would imagine simple masks "might" look like when put to use. One to lighten or darken the edges of the contact print being exposed. I surely wouldn't want to reinvent the wheel if this method of contact printing was already in wide spread use.

9724997250

[polyglot]

I think it's a perfectly reasonable thing to do, I just don't contact print. I had considered something similar, i.e. insertion of an LCD in front of the film plane in order to implement a high-res digital ND masking filter. That approach is probably better for digital systems where you have a digital capture device that can be used to generate the ND mask directly.

Note also that with VC paper and the use of different colours (green, blue), you can also create different contrast in different parts of the image. If you were feeling particularly clever, you could write some software to semi-automatically generate contrast and dodge/burn maps directly from a low-res scan of the image; with a calibrated process (i.e. known paper curves), you could simulate the print results digitally and show the effect of manipulations as they're composed into the mask.

And the approach is not limited to contact printing. You can stick a 7" LCD above your negative carrier, just out of focus, and get the same effect.

[DannL]

I can see one problem already. The display's backlight would probably fog the paper in a short time, even with the display set to all black.

[pherold]

I know some folks at a company in Seattle that 8 years ago invented a high production silver-halide printer that operates something like this. They had a clear LCD that would display an image, and a custom-made array of LED's to act as a backlight. Then the whole business was projected through a lens onto the paper. The Europa printer works very well; has something like 400 dpi. I'm sure it's more that what you're looking for - but you asked if anybody has done this.....
http://www.express-imaging.com/products/europa.htm

[polyglot]

I can see one problem already. The display's backlight would probably fog the paper in a short time, even with the display set to all black.

The whole point is to expose the paper, no? It's like complaining that an enlarger will fog the paper.

See also the DeVere 504DS.