Dan,
Someone recently gave me this source. I haven't used one yet.
http://www.lightboxes.us.com/cat3.asp?ID=21270
They ain't cheap with a $500.00 price tag for a 30x40! But they appear to be well made.
If I really go down this road for a major project I'll look into having some custom made or try it myself. There is a lot for me to learn in that regard.
Anyone making their own? Sven might speak up here. Apparently his project was custom installed ceiling 5000 k tubes with a diffuser between the transparency and the light source. This should work on the wall vertically as well for such an installation.
John
You're right, it's very custom. But it's not a diffuser between, it's the Epson film with it´s milky back mounted on the glass.
The tubes are made in Italy and connected in one long series, dimmed by an electronic device following the 24h light circle.
Brighter at daytime and duller during nighthours.
Speaking about lightboxes, I've made some tests with LED-light, and they give a beautiful approach. (very ugly frames, though).
See attached image. Look out for uneven light, the one that found best, was manufactured in Germany and, of course then, the most expensive. Example; 27x39", $450. The other two tested was from China.
The Epson Trans Backlight film is something in its own class. Extremely large gamutvolume and high sharpness. Also very special when printed as B&W, as in my test. Perfect shine for my winter scenes !
/Sven