I had a hard time researching this topic, so when I finally built my light table I was very proud of the results. I know how frustrating it is, so I'll share the info. I just made a home made exposure unit from stuff i bought around town. My exposure time is 6 min. I used 4 40 watt black light bulbs (Not black light Blue bulbs, like you see at some stoner's house.) These bulbs look just like regular fluorescent, but do not have the 'visible light' filterers that make black lights that deep violet color. I found them at a local lighting supply distributor. They cost about $11 each. You can find a fixture that holds 4 40 watt bulbs and includes the ballasts and light diffuser screen for $40 at Lowe's. Then I just built a box and stand, and put a piece of glass over it. You can get a piece of glass cut at any glass / window place. the dimensions i needed were 23 3/4" x 37 3/4" (the same as the outer dimensions of the fixture i bought). Then I just cut a cheap extension cord and wired it up with a light switch. It works great.