"Ignoramus8325" wrote in message
...
I bought two used metal halide lights. They are about 1x2x0.5 feet in
size and take 250 watt bulbs.

I tried one of the two I bought (the second has a problem, likely due
to shipping, that I hope we can easily rectify with the seller). I
laid ot on the floor and directed the light at the ceiling.

My first impression is that, first, they take quite a while to warm up
(not a problem), and second, they are not that bright.

The color rendering index of MH bulbs is inferior to good fluorescent
fixtures, lumen degradation over time is much greater, and lumen output per
watt is lower. The advantage is you have less fixtures for a given large
space. They will perform in very cold weather, so for unheated northern
shops MH might help. The other application might be right over a machine, to
achieve a higher localized intensity than fluorescent. Currently, gymnasiums
are being changed from MH to T5 or T8 high bay fixtures at a lower wattage
per foot and more natural light.