Is there so such thing as TOO much light?

HydoDan

Well-Known Member
not all LEDs give of less heat. the cheap ones sold on E bay produce about as much heat as CFLs. high end LEDs may produce a little less heat than HIDs or T5s in the 400 watt range in a tent that small 300 watts of actual power should work fine but with only 5 1/2 feet of height to work with you may not be able to get cobs far enough away from your plants to get even light distribution. a 315 lec may be a better option in that size of tent
My 300 watt 3590 6 cob light runs my tent at 74f... without the reflectors on I have it 12" from my canopy.. less than half the heat from a 400 w hid.. No dead or burned leaves!!!
 

Uberknot

Well-Known Member
My 300 watt 3590 6 cob light runs my tent at 74f... without the reflectors on I have it 12" from my canopy.. less than half the heat from a 400 w hid.. No dead or burned leaves!!!

Running at 50w each at 12"? Hell If I did that my plants would fry with my 4 cobs.

As a matter of fact I can go to about 37w 1.3-1.4 mA or so each at 24 inches. 2 x 2 tent 5.5 feet tall.
 

datshieeet

Active Member
Definitely. One of my lights is 38-40 watts per square foot, and the other is 47. The one that gets 38-40 watts is more than good enough; I'd be happy spreading the other one out to cover more square footage too, if I could. But I can't, because it's a tent. I consider a lot of that light wasted watts; i'd rather have a slightly larger footprint and spread the light out a bit.
Unfortunately I too am confined by space restrictions. I am pretty sure I'm going to go with an LED light, I know nothing about LECs. BUT I will check them out before I make any purchase.

Now that I know a good average is about 50watts per square foot, I realize that the one I was about to purchase will be too strong for that area. Thanks for the info!
 

HydoDan

Well-Known Member
Running at 50w each at 12"? Hell If I did that my plants would fry with my 4 cobs.
As a matter of fact I can go to about 37w 1.3-1.4 mA or so each at 24 inches. 2 x 2 tent 5.5 feet tall.
I wonder why we are getting such different results?? I have a 48" bar with 6 cobs spaced at 8"
The plants were vegged outside for 3 months.. I brought two inside and cut them to fit into a 2x4x7 ft.
Tent. That was three weeks ago and I hope they don't get any bigger..lol I'm topped out!!
Is your power supply mounted to your frame?? I have mine outside the tent...idk??
 

Uberknot

Well-Known Member
I wonder why we are getting such different results?? I have a 48" bar with 6 cobs spaced at 8"
The plants were vegged outside for 3 months.. I brought two inside and cut them to fit into a 2x4x7 ft.
Tent. That was three weeks ago and I hope they don't get any bigger..lol I'm topped out!!
Is your power supply mounted to your frame?? I have mine outside the tent...idk??

Whats your power supply? mine are about 6-7" apart.

It might be to to space and reflective light.

875 mA I am at 20,000k lux at the top of the pots from 32"
 

Uberknot

Well-Known Member
My power supply is remote outside the tent... hlg 320 1400 amp

OK so it's set at max all the time 1.4 amps? 12 inches is really close for that amount of power.

AT 1.75 A I get over 78,000 lux at 24 inches. 1.4 A about 56,000 lux at 24 inches.

4 cobs on a 240 1750 this is a testing pic.....temps are not a problem as long as I run the air.

But the amount of light is......can cook the leaves...if not far enough away I am still learning how to set it.

That is a 12 inch square piece of 1/4" thick 6061 type grade aluminum.

IMG_0471.JPG
 
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HydoDan

Well-Known Member
Oh shit forgot about the dimmer.. does that adjust amps? Watts? I know I'm really to close but I just want these to finish so I can stat my first full cob grow. I've had a couple half bleached leaves.. nothin bad tho
 

Uberknot

Well-Known Member
Oh shit forgot about the dimmer.. does that adjust amps? Watts? I know I'm really to close but I just want these to finish so I can stat my first full cob grow. I've had a couple half bleached leaves.. nothin bad tho

Yeah dimmer adjusts how bright it is and how much amps.
 

Uberknot

Well-Known Member
Ok, I got a real lux meter today so I am testing atm....a tablet lux meter is not very accurate when used around an area like a lux meter from everything I can tell. Also those peak readings I was getting are only in the very center of the lights straight down it's like a hot spot there. ATM testing with max 1750 mA and getting around 55k-60k at 24 inches. If I move the lux meter to 12 inches maxed 1750 mA I get around 110,000 lux SO it's not quite as bad as I thought thank god....
Now back to testing! :P

I can say this much I am so glad to have a light meter right now! ;)
 
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HydoDan

Well-Known Member
Ok, I got a real lux meter today so I am testing atm....a tablet lux meter is not very accurate when used around an area like a lux meter from everything I can tell. Also those peak readings I was getting are only in the very center of the lights straight down it's like a hot spot there. ATM testing with max 1750 mA and getting around 55k-60k at 24 inches. If I move the lux meter to 12 inches maxed 1750 mA I get around 110,000 lux SO it's not quite as bad as I thought thank god....
Now back to testing! :P

I can say this much I am so glad to have a light meter right now! ;)
I just made the change to cob leds and haven't had enough $$ to get a light meter or watt meter..
spent all my $$ on the cobs.. Lmk on the testing!
 
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