Vertical light radius? - Vertical / Colosseum Growing - International Cannagraphic Magazine Forums

10-28-2007, 08:58 AM

The specs on the 400w hps I have state it has a grow area of 4 x 4 ft. Secondary (?) light to 6 ft by 6 ft.

If I hang my bulb vertically, will it throw light in a radius of 3 ft, or 6 ft?

Also, if I had 4 plants around a central bulb, and spun them 1/3rd around each day, would this provide enough light?

TGT · 10-28-2007, 09:10 AM

You could probably do the four plants with a 400 watt vertical HPS with small plants, but I wouldn't go too large. I have always prefered vertical, but I have never done it with a 400, so hopefully somone else with more experience can chime in.

TGT

Harry Gypsna · 10-28-2007, 10:58 AM

ive been wondering about the actual perfect area for a 250...like i know a bulb has a sweet spot 360 degrees around a the bulb..sort of optium distance.... Im just not sure what that is and what i have n mnd it s vital coz every inch will count.

10-28-2007, 11:13 AM

i feel like if you can keep everything about 18 inches from the 400 in a vertical setup it should reach the best ratio between lumens at the plant and plants reached

but just guessing because i haven't actually run one........sorry

10-28-2007, 05:40 PM

With the 400W HPS the closest without over lighting the plants is 9 inches for approximately 9,000 Foot Candles of light, to 18 inches for 4,000 foot Candles.

Notice the exponential drop in FC's at 18" vs. 9". This formula applies irregardless of the wattage of the lamp(s) used.

10-28-2007, 05:47 PM

What I would do is, setup the plants next to the bulb and take the leaf temperature with one of those laser thermometers. The leaf temps to hot? Just move the plants back until you get to that sweet spot. If your only using a 400w, I would much rather be concerned with the temps rather than light output.

my 2cents

C21H30O2 · 10-28-2007, 08:12 PM

im running a bare bulb 400 w grow. ive got foliage within 2 inches of the bulb with no burning or bleaching. i simply placed a fan blowing under the bulb straight up the bulb still produces heat but it is quickly carried to the top of the grow area and sucked out the top.

10-28-2007, 08:21 PM

Thanks everyone.

Once the plant/ers are in there's no moving em. over 100 kilos each on custom built floor to take them (grow in basement).

I'm going to aim for a 3 ft radius. meaning, the plants will need a diameter of 4' 6" to come within 9 inches of the light. They can grow 2'3" from the central stem before I have to do any tying.

A large fan will be blowing directly onto the light and another fan pulling air out of the room that i've grown in with the 400 for several years. And yes, it does get too hot, but only in the height of summer, and only mould etc if I use a non local-crossed strain. My grow method has a better temperature buffer than normal, which helps. Our humidity can get over 90% outdoors sometimes, so I guess the weed is used to it by now.

If the vertical lighting gets good results I'll post back here with the new set-up for dissection.

Thanks again.

asshole · 12-18-2009, 06:43 AM

Quote:

Originally Posted by Harry Gypsna

ive been wondering about the actual perfect area for a 250...like i know a bulb has a sweet spot 360 degrees around a the bulb..sort of optium distance.... Im just not sure what that is and what i have n mnd it s vital coz every inch will count.

can anyone answer?

12-18-2009, 12:28 PM

https://www.icmag.com/ic/showthread.php?t=128613

this will help^

10-28-2007, 08:58 AM	#1
Guest Guest Posts: n/a	Vertical light radius? The specs on the 400w hps I have state it has a grow area of 4 x 4 ft. Secondary (?) light to 6 ft by 6 ft. If I hang my bulb vertically, will it throw light in a radius of 3 ft, or 6 ft? Also, if I had 4 plants around a central bulb, and spun them 1/3rd around each day, would this provide enough light?
	Quote

10-28-2007, 09:10 AM	#2
TGT Tom 'Green' Thumb Join Date: Oct 2006 Location: Purgatory Posts: 1,846	You could probably do the four plants with a 400 watt vertical HPS with small plants, but I wouldn't go too large. I have always prefered vertical, but I have never done it with a 400, so hopefully somone else with more experience can chime in. TGT __________________ Life is like a toilet paper roll, the closer you get to the end the faster it goes.
	Quote

10-28-2007, 10:58 AM	#3
Harry Gypsna Dirty hippy Bastard Join Date: May 2004 Location: Outside BodyShop, with a Tin Whistle and a dog on a piece of string Posts: 8,157	ive been wondering about the actual perfect area for a 250...like i know a bulb has a sweet spot 360 degrees around a the bulb..sort of optium distance.... Im just not sure what that is and what i have n mnd it s vital coz every inch will count. __________________ Clowns to the left of me, jokers to the right, and none of these people are very funny.
	Quote

10-28-2007, 08:12 PM	#7
C21H30O2 I have ridden the mighty sandworm. Join Date: May 2007 Location: Babylon Posts: 1,229	im running a bare bulb 400 w grow. ive got foliage within 2 inches of the bulb with no burning or bleaching. i simply placed a fan blowing under the bulb straight up the bulb still produces heat but it is quickly carried to the top of the grow area and sucked out the top. __________________ F1 or inbreed/landrace strains only, NO POLY-HYBRIDS!!
	Quote

10-28-2007, 11:13 AM	#4
Guest Guest Posts: n/a	i feel like if you can keep everything about 18 inches from the 400 in a vertical setup it should reach the best ratio between lumens at the plant and plants reached but just guessing because i haven't actually run one........sorry
	Quote

10-28-2007, 05:40 PM	#5
Guest Guest Posts: n/a	With the 400W HPS the closest without over lighting the plants is 9 inches for approximately 9,000 Foot Candles of light, to 18 inches for 4,000 foot Candles. Notice the exponential drop in FC's at 18" vs. 9". This formula applies irregardless of the wattage of the lamp(s) used.
	Quote

10-28-2007, 05:47 PM	#6
Guest Guest Posts: n/a	What I would do is, setup the plants next to the bulb and take the leaf temperature with one of those laser thermometers. The leaf temps to hot? Just move the plants back until you get to that sweet spot. If your only using a 400w, I would much rather be concerned with the temps rather than light output. my 2cents
	Quote

10-28-2007, 08:21 PM	#8
Guest Guest Posts: n/a	Thanks everyone. Once the plant/ers are in there's no moving em. over 100 kilos each on custom built floor to take them (grow in basement). I'm going to aim for a 3 ft radius. meaning, the plants will need a diameter of 4' 6" to come within 9 inches of the light. They can grow 2'3" from the central stem before I have to do any tying. A large fan will be blowing directly onto the light and another fan pulling air out of the room that i've grown in with the 400 for several years. And yes, it does get too hot, but only in the height of summer, and only mould etc if I use a non local-crossed strain. My grow method has a better temperature buffer than normal, which helps. Our humidity can get over 90% outdoors sometimes, so I guess the weed is used to it by now. If the vertical lighting gets good results I'll post back here with the new set-up for dissection. Thanks again.
	Quote

12-18-2009, 12:28 PM	#10
pine boy Guest Posts: n/a	https://www.icmag.com/ic/showthread.php?t=128613 this will help^
	Quote