>...I am willing to sacrifice a little bit on exposure time
> and place the paper further away ... will that give even exposure?... Do you think with 4-5 inches distance (and
> four 20W bulbs),...
> Also, the black-light tubes is 20W each....
Placing the bulbs further away will not sacrifice very much printing speed until you get pretty far away. Almost no loss until the distance exceeds the minimum width and then only minimal. The sqare of the distance law is only for *point sources* For that to be in effect you would have to be far enough away from the light bank for it to appear for all practicle purposes as a point source, say 25 to 50 feet. I think it was Bob Schramm who worked out the math on this last winter for us when the topic came up. Likewise if the tubes are close together, you can lay the print frame directly on them with no visible banding. Weird I know but it works.
Bostick & Sullivan
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