How far are your 1000w bulbs?

So I am still trying to finish our flowering room and will be using 1500w hps bulbs hung open air vertically. I am trying to gauge how big to try to make our screens around the bulbs. I had found a post with lumen chart and distance from bulbs. It would seem the optimal distance would be about 13 inches, so I would make a 26 inch screen around the bulbs. But is this too close? How close are your bulbs?

its not 13 inch, because even thought that may be 100% lumen efficiency, when adding one more distance, it can be times by 3.14 (pi*diameter), thus when adding 6 inches to the distance on both sides, or 1 foot in diamter, the allowable plant area to grow under light is 12"*3.14, meaningf extra 36 inches, now times that by the lenght (height in our case) and the numbers start to take off. I believe a 600 w that i saw was 1.5 feet away from bulb, but I have never done vert, just know 13 inches would not work good at all.

more help from the experts ?

OK, thanks, that is a good start. Anyone else.

the ratio of my cage is 17 inches and I still think is too close to the plants.

Maybe this chart could help..

thehiena said:

the ratio of my cage is 17 inches and I still think is too close to the plants.

Maybe this chart could help..

Click to expand...

Thanks! That is way different than the chart that I have. So what do you all think that I should start with for a 1500w bulb?

Maybe about 20-22"... better to not burn em.

some branches of mine are 12" away from the bulbs but between 12-24" they are lovin' it.

anyone else????

I never use 1500 bulbs so i dont know but i do use 1k and i place mine 18 - 36 inches from the light and they seem happy ? some of the one that is closer then 18 get tip burns and such but very minor.

Cheers,

Its not lumens, its heat and the amount of plants that you want to get coverage.

The closer it is, the less plants and the less yield. If you're not cooling then you get burn.

I don't know why you're using 1500w bulbs, they are a bad idea... high inefficient in every respect.

This issue was addressed on a vertgreen thread a week or so ago. You can keep a plant from burning itself from direct heat, however the real problems occur from the plant overfeeding itself, and from light energy building up on the leafsurface. When light hits the surface of the leaf in great intensity it makes the fluids inside the cells boil and rupture. This slows growth signifigantly.

Im a firm beliver in keeping em at least a full 18"

For some reason once the girls finish stretching they can thrive a little closer in, however during veg and early flower i think it is best to keep plants at least 18"

Check out my grow here, look how close i have my girls. This is way to close i think. I have since moved them back with stakes and zipties.

http://www.verticalgreen.org/showthread.php?t=1487

The 1500's aren't as bad as you think, in a flat garden their 206K lumens (137 lumens per watt) cover a 5.5' X 5.5' area pretty well, much bigger footprint than a 1KW light.

As for distance, I wouldn't put them close than about 28-30 inches from the canopy, you're already brighter than the sun at 22".

first time i ran a 1000mh i put it too close to my plants, no burn but plants didnt grow for a week, was in an open basement had plenty of space n air, after i raised the light to about a foot n a half they got happy, as they flowered i brought the light much closer and they never minded.

Lazyman said:

The 1500's aren't as bad as you think, in a flat garden their 206K lumens (137 lumens per watt) cover a 5.5' X 5.5' area pretty well, much bigger footprint than a 1KW light.

As for distance, I wouldn't put them close than about 28-30 inches from the canopy, you're already brighter than the sun at 22".

Click to expand...

Where is the sun ranked in all this?

1500 watt bulbs are stadium lights. They are made and designed to operate in an enclosed fixture, air cooled at a height of hundreds of feet. They are not for indoor use, ever. You are playing with fire.

Well these were made specifically for growing. We aren't retrofitting anything or using something for an application that they weren't intended for. They are experimental and very bright though, so we are playing with fire a little.... hopefully in a good way!

60 cm(2 feet), d

You would know better than I what you have. However, I'm just hoping some slick hydro salesman hasn't yanked your chain.
Do you mind if I ask who makes the ballast and bulbs? I wanna look it up.
Please read the bulb charachteristics I found, particularly the rated life, Lamp enclosure type, and the warnings at the bottom.

http://genet.gelighting.com/LightPr...PRODUCTCODE=47326&BreadCrumbValues=Lamps_High Intensity Discharge^1001 and above Watts&SearchFieldCode=null

47326 – MVR1500/U/SPORTS
GE Quartz Metal Halide BT56 - Sports Lighting



GENERAL CHARACTERISTICS
Lamp type High Intensity Discharge - Quartz Metal Halide
Bulb BT56
Base Mogul Screw (E39)
Bulb Finish Clear
Wattage 1500
Rated Life (Hor) 3000 hrs
Rated Life (Vert) 3000 hrs
Bulb Material Hard glass
Lamp Enclosure Type (LET) Enclosed fixtures only
LEED-EB MR Credit 349 picograms Hg per mean lumen hour
Primary Application Sports Lighting
PHOTOMETRIC CHARACTERISTICS
Initial Lumens (Hor) 162000
Initial Lumens (Vert) 170000
Mean Lumens (Hor) 137000
Mean Lumens (Vert) 153000
Nominal Initial Lumens per Watt 108
Color Temperature 4000 K
Color Rendering Index (CRI) 65
Effective Arc Length 3.700000
ELECTRICAL CHARACTERISTICS
Burn Position Universal burning position
Warm Up Time to 90% (MIN) 2 min
Warm Up Time to 90% (MAX) 5 min
Hot Restart Time to 90% (MIN) 10 min
Hot Restart Time to 90% (MAX) 15 min
DIMENSIONS
Maximum Overall Length (MOL) 15.3700
Nominal Length 15.370
Bulb Diameter (DIA) 7
Light Center Length (LCL) 9 1/2
PRODUCT INFORMATION
Product Code 47326
Description MVR1500/U/SPORTS
ANSI Code M48
Standard Package Case
Standard Package GTIN 10043168473269
Standard Package Quantity 6
Sales Unit Unit
No Of Items Per Sales Unit 1
No Of Items Per Standard Package 6
UPC 043168473262
COMPATIBLE GE BALLASTS
Product Code Description # of Bulbs Power Factor Ballast Factor
86693 GEM150048TAC5-5 1 0.9 1.0
86698 GEM1500MLTAC5-5 1 0.9 1.0
CAUTIONS & WARNINGS
R- WARNING: This lamp can cause serious skin burn and eye inflammation from shortwave ultraviolet radiation if outer envelope of the lamp is broken or punctured, and the arc tube continues to operate. Do not use where people will remain for more than a few minutes unless adequate shielding or other safety precautions are used. Certain types of lamps that will automatically extinguish when the outer envelope is broken or punctured are commercially available. Visit the FDA website for more information: http://www.fda.gov/cdrh/radhealth/products/urburns.html

Cautions & Warnings47326 GE Quartz Metal Halide BT56 - Sports Lighting
CautionLamp may shatter and cause injury if broken Dispose of lamp in a closed container. Do not use excessive force when installing lamp. Do not use lamp if outer glass is scratched or broken. WarningRisk of Electric Shock Do not use where directly exposed to water or outdoors without an enclosed fixture. Turn power off before inspection, installation or removal. Unexpected lamp rupture may cause injury, fire, or property damage Do not exceed rated voltage. Do not turn on lamp until fully installed. Do not use beyond rated life. Do not use lamp if outer glass is scratched or broken. Do not use where directly exposed to water or outdoors without an enclosed fixture. If used on a dimming system, see instructions. Operate lamp only in specified position. Turn lamp off at least once for 15 minutes per week. Use in enclosed fixture rated for this product. Use only properly rated ballast. A damaged lamp emits UV radiation which may cause eye/skin injury Turn power off if glass bulb is broken. Remove and dispose of lamp. Risk of Burn Allow lamp to cool before handling. Do not turn on lamp until fully installed. Risk of Fire Keep combustible materials away from lamp. Use in fixture rated for this product.
See list of cautions & warnings.


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Spectral Power Distribution

They are Sunsystems Master Blasters.... I gotta run, but I will be around later and we can talk about them if you have looked them up...

Thanks!

Sunsystems is made by Sunlight Supply, Inc. I visited their website and found absolutely no 1500 watt items at all. Master Blaster in the search field revealed nothing as well. I did notice that their standard bulbs were all GE products, otherwise nadda.

I went to several other prominent lighting sites as well: Sylvania, Advance, GE. There is very little 1500 watt products out their, and none are different than the one i qouted earlier.

Sorry I don't have anything useful, but it sure seems like that company is using you for a guinea pig. I'd wager none of your 1500stuff is UL listed either. (The Underwriters Laboratory researches all electrical devices).

However, my cooltube isn't UL listed either, and I still use it. With a smoke detector and a fire extinguisher on site, of course.

I've worked with stadium lighting several times, which is where my concern comes from. However, if they tell you its alright. And you don't have any issues, I will happily say I'm wrong.

Good Luck