Positioning Of Light

[Hyperbongluva]

Yo.

 

I'm new to growing indoors and am about to move a plant about a foot high into a cupboard with a 400w hps setup. Was wondering exactly how high above the plant the light should be positioned?

[OldmanMozz]

put ya hand, palm down, under light, at top of canopy, leave for couple minutes, if its to hot for ya its to hot for ya ladies

 

 

cheers an cones Mozz

[white_cluster]

yeah what mozz says is the way to go, I keep my 400's at about 40cm in flower, but dont listen to that. Was sitting in chat a few weeks ago and the topic came up and 4 different growers had 4 different distances.

So go with the hand unless you one of them people who cant feel anything.

[Medicalman]

One thing to think of is to let your plants adjust a bit to the new lamp. I start mine off at about 2 feet for 2 days then lower the lamp by 3 or 4 inches per day. A little distance means a lot in terms of light intensity.

 

If you have 55,000 lumens at 1 foot from the bulb, you'll only have 13250 at 2 feet and 6100 or so at 3 feet. Its called the inverse square law of light.

 

With good temp control and ventillation and circulation, I have been able to get my 400 within about 8" of plant tops without burning. But that depends also on the strain, some are much more tolerant than others. I have grown other strains where the 400 did some light damage at 1 foot.

 

 

Best

MM