my 400 watt hid doesnt look very bright?

i got 3 ceiling shop lights for a hugh shop that are 400 watt mercury vapor lights i think with balest built in but they dont seam to be that bright.i never saw how bright it should be when close to the ground but i was wasndering if it should look really bright or if it was powerfull but not blindingly bright like i would imagine.any info would be nice its wired strait into the house wireing were the ceiling light was.

thanks

dont use mercury vapor. use metal halide or high pressure sodium and you will be fine.

yep. mercury vapor lights are entirely the wrong spectrum for growing. not to mention they put off a lot of heat.