LED panel for contact printing?

[hadeer]

Is there anyone who has experience in contact printing with one of those slim LED panels? I wondered if it is possible to use such a panel directly sandwiching it with a digitally printed negative and the photo paper. Kaiser for instance makes the Slimlite plano led light box 32x22.8 cm. That would allow prints up to A3 size. Thanks for any input.

 

[koraks]

The light intensity of those panels may be an issue with most printing papers except dedicated contact printing papers such as those made by Adox and Foma. With a precision timer allowing e.g. 0.1 second exposure it may work, and/or with the leds hooked up to a pwm dimming circuit.

 

[hadeer]

Thanks Koraks, I see your point. Currently I am using my enlarger as a lightsource to contact print on Adox baryta and Foma for making traditional and lith prints respectively. Without the possibility to control the exposure time that would make no sense.

 

[ic-racer]

Better with a point source (clear globe lamp) far from the printing frame. Once you add in multiple point sources (like a frosted globe or flat panel) there will be overlap of the rays in the middle of the print with the tendency for a hot spot.

 

[Michael Firstlight]

I use my flatbed to make contact prints. I don't understand why going through a wet print process is valuable unless one doesn't have a scanner - even a cheap used flatbed with a transparency option is faster and cheaper. I don't see how a wet contact print can be effectively used to determine enlargement exposure. Maybe someone can enlighten (sorry for the pun) me as to what the benefit is otherwise as my PrintFile contact printer now goes unused.

MFL

 

[koraks]

I don't understand why going through a wet print process is valuable unless one doesn't have a scanner

Well, that's true if your end goal is a digital image. I think for many people who are doing wet prints, the prints are the end goal. For me they are, but that's just my perspective of course.

 

[hadeer]

the prints are the end goal

That is exactly what I am trying to do. I never met a digital equivalent for a genuine lithprint. I need the digitally printed negative on a transparency because frequently a file from my digital camera is the source. But yes, still experimenting with the wet process.