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I know I'm new here but I wanted to share these bud shots that I thought fit this thread. These Jack Herer x Herijuana nuggs were grown under a 400 W CMH bulb. I have a freind who grows under CMH and I am out to get one real soon. He has huge yeild and high potency.
wow very nice. way better than the jack i had under hps
but could be strand i got & light,
the grow was fine & she was happy but they not look as fine as above.
sweet.
Are you serious? Electricity doesn't come built in with the bulb?
LOL. Seriously though, I did need it laid out plain and clear. I don't wanna buy something and then have to buy something else... and then something else... and then...
Rip, havent forgotten i just deciding how to type that up for the short version.. its simple yet i go into heavy twisty detail to fast.. LOL
Mr, B D
ya no worries man its just that Q is asked over and over and we all get a bit touchy sometimes..
if u got a SS10 S51 u good.. Screw and go.. LOL..
winter,
that is a HPS lamp not a CMH lamp.
all HPS use Ceramic Arc Tube. and filled with sulfur/etc
all metal halides are Qaurtz arc tubes with Metal/Halides/etc.
All CMH are Ceramic Arc Tubes with Metal/Halides/etc
hence the CMH is a Combination of both bulbs in one format.
thats another reason why we say the Philips HPS Retro WHites are not Conversion Bulbs as we usto know them to be. as its both hps/mh in one therefor the starting/running requirements are very simular and only small modifactions are needed to make a standard CDM400/V (standard cmh using MH Ballast) Vs CDM400S51 (hps retro white using hps ballast.)
there are minor differences but nothing like a conversion bulb.
short note..
there wont Be a 1KW CMH that i would ever recommend to any one in a consumer setup.. (unless a New arc tube design comes out)
Thats a bit harsh to say but if a cust has a 1kw mh they could use a 700CMH when they come to be reliable/avail...
if you are a comercial ap you can go from 400 MH Or HPS to a 320CMH and get better light.. Not as intense IE Blinding when you look at it.. but it lights all up and you can see detail.. and the lumen maint is sim to HPS so it stays brighter a 400 MH will be dimmer than a 320 cmh at end of life.. Short version..
when CMH Goes its not the same as MH or HPS..
when MH Blows the Qautz arc tube has no weight to it and shaters basicly so it doesnt go far or penetrate.
when a cmh goes its generally the seals that go (seen few few few pop an arc tube)
but when the seals go (most common failure) it Goes like a ROCKET as ONE PEICE.. it also weights about 8grams and doesn't break even when Slammed down on table. (i have only shatterd them when Slamming to Concrete)
with that said the Ceramic Arc tube is Ceramic so it HOLDS HEAT (thats one beni of cmh.. as it contains and allows most heat to radiat up>>>.
so with all that said.. SHort ay?? LOL
if you compare the arc tubes in CMH in all the wattages 10-700W they go up in size and pressure proportionately when it pops propelling it even further or in 500+W actually BLOWING The arc tube UP as its most common reason for premature failure (seen the 680W CMH only Blow SCARY, and was i was protected..)
thats another reason philips has it with the protected versions.. (i have never seen a Philips Arc Tube make it out of the outer Jacket.. )
http://advancedtechlighting.com/cmhfact3.htm
If you notice there pic below the arc tube is in one peice and if you ever seen your CMH right after u turn it off its HOT For a while and after you cant see the RED anymore it still can light a cigarette for a minute or so..
Edited:
super short version
Lumens dont = Growth.
lets take a lamp that is kinda Mono chromaticish..
Lumens
Blue=3,450
Green=6,900
Red=1,500
there about = in actull side by comparison vs energy used vs output..
green aint growin dirt.. is it.. so lumen isnt the only reference one can go by...
so back to your Q
400cmh3x4ft supersun 1or 2 zoned down coverage.
4x4 using square LumenMax (its the best for a single 400 if not AC if AC you need to go with a sungro..
all from From NGW
SS could be used in a single setup under 3x4 sog/vine crops.
in a small area you want your walls to reflect as much light as possible and you want a bit of light to hit the walls and come back (if you can for super efficient setup) Unless you are keeping growth neat and Pruned directly under)
I'm doing all I can afford right now to control temp and I'm in the high 80s low 90s as it is right now with a 400 watt HPS.
I have read repeatedly through this thread that the CMH throws heat different and I can expect to be able to bring the plants closer to the light source.
Someone must have experience on switching from HPS to CMH and the difference in temp experienced.
With a 400 watt cmh (no glass, not air cooled) my temp temperatures are 3 degrees (f) higher than the rooms ambient temp. Which is a couple of degrees cooler than using the air cooled and a hps bulb.
Note: i have and oscillating fan and a 6 inch Fantec exhausting at full speed in a 3'x3'x6' tent.
Great, thanks! I'm stoked. I was debating just getting a new hood that I can air cool my HPS, but sounds like CMH will be more efficient solution to my heat issue
It may sound that way, and I may sound like a pain to you, but don't count on your light to help with heat issues. You have ventilation that needs addressed.
Only folks with grows that have control of the ventilation and temps can think about moving the plants closer.
I would spend my money on proper ventilation for the grow first. An air cooled hood will probably help loads, but a fan and proper intakes will help more.