Originally Posted by DreadedHermie
1.5 feet's prolly good. If you had it real close before that might have been the problem. Try this: turn off the other lights in the room and start out with the UFO on, and real close to the floor. Now slowly start raising it up and watch what happens to the light footprint. Does it stay pretty tight as you raise the light, like the beam of a spotlight? Or does the light spread all over quickly as you raise the light, with a softer pattern?
If the beam stays tight, they've prolly got those emitters lensed @ 60 degrees or less. Lights like that you treat more like a HID--you can (should) get further away to let the light spread out a bit. The beam stays tight and the light hits hard and gives better penetration. Procyons are like that. Get 'em too close and the plant just stands still.
If the light is evenly distributed and spreads all over the place as you raise it, you may have "lambertian" light distribution pattern, which simply is a 140 degree spread. 180 degrees is everywhichway except backwards, so that's as wide a beam as you're likely to encounter. Lights so equipped work best if you use 'em like flouro tubes-- gotta get as close as you can, but because the LED's are so cool running you can get real close. These lights give excellent coverage and are very even and very forgiving.
I like 'em, myself (well, up to 90 degrees or so) but if you get them too far away it doesn't seem like they've got any ooomph at all. If you try to run them from 18 inches away they scatter the light all over the place, and seem totally weak. 3-6" is more like it with hi-power diodes. You can get the low power ones almost touching, but that's a PIA.
Give it a try and let us know how the light spreads.
I couldn't find a quad-band seller on the Bay with that many feedbacksa, so I still don't know which model you've got. And no LED manufacturer that I know of makes anything called dark blue. Deep blue, maybe?