jadins_journey
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- Joined
- Oct 1, 2008
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- 263
I had a bulb and ballast in the garden the other evening for a buddy to make sure it works like it did when I took it down. There has been a good amount of talk lately about vertical placement of bare bulbs in grow rooms so I figured since this bulb was fired up and suspended above the plants I would get out my light meter and see just how well it preforms. It was my honest intention in doing this little project to prove to myself that I could take down my sealed reflectors, turn off the fans and run a bare bulb system atleast during the winter months.
Measurements were taken off of a 3' x 4' footprint. I took 12 measurements spread out acorss this 12 square foot area at equal distances. All measurements were taken from 13" below either the bottom of the bare bulb or 13" below the bottom of my reflectors. I tested all three bulbs (MH, HPS, and Dual Arc) in the same reflector fired by the same ballast, all bulbs had 15 mintues of warm up time before measurements were taken. Room temp was 71F and RH was 45%. Granted I only tested BELOW the bare bulb as that is the only way it could fire in my system.
MH Bare
range 750 - 1700 FC
avg. 1083 FC
MH in Reflector
range 600 - 4600 FC
avg. 1891 FC
Dual Arc in Reflector
range 700 - 4500 FC
avg. 1550 FC
HPS in Reflector
range 1000 - 6500 FC
avg. 2830 FC
This research is based on finding the most efficient means of useing light power, not a discussion on spectrum as that decision is based on bulb type not mounting position. I am fully aware that reflectors suck as far as distribution goes, the range numbers alone prove that. I am also aware that one reflector can suck much worse than another as the one in my veg system is proven to put out 30% more light power than the ones I have in flower fired by the exact same equipment, tested that long time back but not enough cash to upgrade now.
This little project took me about 3 hours the other night and it COMPLETELY changed the way I ventilate my grow room. Each of my reflectors have a 425 cfm fan attached inline to vent out heat. I turned off the fans, removed the glass in my reflectors and am running a modified bare bulb system LOL, no fans but I am keeping the reflectors where they are, room temp is exactly what it was with the fans and glass. Next step is to tame that room exhaust fan down some with a variable speed controller.
Best of luck,
jj
Measurements were taken off of a 3' x 4' footprint. I took 12 measurements spread out acorss this 12 square foot area at equal distances. All measurements were taken from 13" below either the bottom of the bare bulb or 13" below the bottom of my reflectors. I tested all three bulbs (MH, HPS, and Dual Arc) in the same reflector fired by the same ballast, all bulbs had 15 mintues of warm up time before measurements were taken. Room temp was 71F and RH was 45%. Granted I only tested BELOW the bare bulb as that is the only way it could fire in my system.
MH Bare
range 750 - 1700 FC
avg. 1083 FC
MH in Reflector
range 600 - 4600 FC
avg. 1891 FC
Dual Arc in Reflector
range 700 - 4500 FC
avg. 1550 FC
HPS in Reflector
range 1000 - 6500 FC
avg. 2830 FC
This research is based on finding the most efficient means of useing light power, not a discussion on spectrum as that decision is based on bulb type not mounting position. I am fully aware that reflectors suck as far as distribution goes, the range numbers alone prove that. I am also aware that one reflector can suck much worse than another as the one in my veg system is proven to put out 30% more light power than the ones I have in flower fired by the exact same equipment, tested that long time back but not enough cash to upgrade now.
This little project took me about 3 hours the other night and it COMPLETELY changed the way I ventilate my grow room. Each of my reflectors have a 425 cfm fan attached inline to vent out heat. I turned off the fans, removed the glass in my reflectors and am running a modified bare bulb system LOL, no fans but I am keeping the reflectors where they are, room temp is exactly what it was with the fans and glass. Next step is to tame that room exhaust fan down some with a variable speed controller.
Best of luck,
jj