air cooled HPS lamp height???

hey
I've been looking at upgrading my grow and getting a 600w hps. The air-cooled hps's are quite alot more exspensive but would it be worth it? and how much closer can you place the lamp on your plants? what is your experiecne with air-cooled hps's?
rep> for gud info
cheers

I use 4 x 600 watt hps XTRASUN aircooled hoods with a 6" centrifugal pushing out and a double 4" vacuuming in. With these aircooled hoods i can seriously get away with about 6 inches away...i will take pictures when the light comes on today, and put them on here for you to see. But this is a very talked about subject, and alot of people are mis-informed on what you can and can't do. But i reccomend watching the "seemorebuds" videos...He goes through several different gardens in each video and it gives you different ideas of different techniques to use. Every grower is diff with our own ways you know. But i used to do the reccomended 18 to 30 inches away with my HID's and did great. Had the average results everytime, never had weak yields, always average and slightly above. Moved my lights down and started moving the air more...guess what? DOUBLED MY YEILD EVERY TIME!!!!! But with anything you should take special care and consideration according to YOUR room and plants. I grow Sativa doms, and supplement co2 witch allows me some higher temps, and the strains geno plays a matter into this...but to answer, you can get closer than the usual 18 to 30. I'll show you how close later.

^Agreed. Intensity = yield. I run my non-cooled 600 HPS about 14" from the top of the plants that are directly underneath it, and it works out to about 22-24" from the plants at the outer edges. I have a 14" oscillating fan running constantly, sweeping across the upper half of the plants, with room temps in the lower 80's(not by choice.lol) and never had any problems with heat stress/damage. That was during the wonter months, when heat was easier to control.

I switched to air-cooled hoods, now that it's warmer outside, and I still like to keep it at about 12", for the extra light dispersal. I could run it really close if i wanted, 6" or less, but then the light would only be covering a tiny area. In my mind, there's a sweet spot that'll give you the best balance of intensity and coverage, therefore...yield. I say this because at 10-12", the light intensity is up around the 10,000 LSF(lumens per square foot) level, and figure that running it closer would be wasting energy that the plant can't use(I don't run CO2). These are all just theorys though, as I haven't even finished my first grow yet, with the air-cooled reflectors. Time will tell.

thankyou for the replies! after consideration i've decided to go with a normal hps but fit a whole new larger extraction system. i might save up for a water cooled hps when i can get a bigger set-up. thankyou for the advice!