How far should MH light be from plants?

[VACAVILLE,CA.GROWER]

Hello, I have 5 autoflowers inside a 32x32x63 tent.
I am using a 400 watt mh/hps light with a dimmable ballast.
My plants are 2 weeks old in 2 gallon smart pots with ocean forest soil.
I have my let set at 1/2 the watts, so 200 watts.
My light just has a wing reflector.
What distance should the light be above my plants?
Any help would be great.

 

[Kcbscrogger]

Hello, I have 5 autoflowers inside a 32x32x63 tent.
I am using a 400 watt mh/hps light with a dimmable ballast.
My plants are 2 weeks old in 2 gallon smart pots with ocean forest soil.
I have my let set at 1/2 the watts, so 200 watts.
My light just has a wing reflector.
What distance should the light be above my plants?
Any help would be great.

 

[Jon E. Doe]

Yep, the starting point will generally be what the engineers recommend.

 

[LetsGetCritical]

about a foot, but i'd raise any lamp over having heat concerns

 

[LetsGetCritical]

don't bother dimming a 400w. 400watts is not that much with to begin. What is the light schedule incidentally?

 

[harris hawk]

start at a foot - use back of hand test to determine if light is too close or too far a-way ( 500 watt cfl's can be placed 6-8 inches from plant)