Seeking advice on a specific UV lightsource

[Photopathe]

Hi! I want to get a UV light source and was thinking about buying a 1000w metal halide lighting system, from a non specialized store. I would then be looking to buy or try to make a vacuum printing frame. But I saw this product on ebay. It features a vacuum frame. Seems quite interesting but I don't have much experience and would like to have some advice or opinions about it before buying.
Here follows the link.
Many thanks!

https://www.ebay.ca/itm/50cmx60cm-2...e=STRK:MEBIDX:IT&_trksid=p2055119.m1438.l2649

 

[Sirius Glass]

Let me welcome you to coming to the right place for advice. Welcome to APUG Photrio.

 

[Photopathe]

Thank you!

 

[nsurit]

It will be interesting to hear what others have to say. I've built a couple of exposure units of similar size (24"X24") which don't include the vacuum frame and the cost of materials run about $400. You could probably find a used plate burn for a bit less, however it would likely take up a bunch more room.

 

[Photopathe]

I am leaning toward the unit I linked to. One of the things that concern me in the specs of that unit though is 85% illumination uniformity. Good enough or lack of uniformity will show on print? Is this a good rating?

 

[brent8927]

I built my own UV light source using some high UV-output fluorescent bulbs from a lighting store. It worked quite well, other than taking a while to expose (I'm guessing these UV light sources have higher UV output).

In the end, I decided the sun worked much better. But I did live in CA at the time. While UV light goes through clouds, the cold temperature in Montreal would probably affect the exposure quite a bit (maybe halt the chemical reaction?)

Depending on how long of an exposure is required, you may be able to work around the uneven illumination by just moving the print around a bit. This assumes you're using a contact printer to hold the negative and paper against each other like I was using, as you can move it and it won't blur the image. I've never used one of the units you linked to, so I'm not sure how the exposure is handled.

 

[Bob Carnie]

I am leaning toward the unit I linked to. One of the things that concern me in the specs of that unit though is 85% illumination uniformity. Good enough or lack of uniformity will show on print? Is this a good rating?

I really like your original idea, as the power will be huge, and with a system for regulating exposure you can put any size vacuum unit below. will follow your thread, so you mind posting the Metal Halide 1000w unit info.

 

[Photopathe]

I will denifitely keep you updated and write about the final result no matter what option I choose.
Meanwhile I found some more details about the uv printer:
http://www.printermaker.com/Vacuum-UV-Exposure-Unit-p1045.html
Quite tempting!

 

[Photopathe]

BTW, how easy or difficult is it to build a DIY vacuum frame?

 

[pschwart]

- depending on your chosen process and workflow, you might find the 999 sec timer insufficient
- I would want to see more details about the output spectrum and distribution
- illumination uniformity of 85%: this would worry me