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Ceramic Metal Halide (CMH)

MPL

Member
I've got a thread in the infirmary from where I was trying to figure out what was wrong with them. You can check it out but the last pics are pretty old and they're looking a lot better now.

clicky

I guess it's a sort of a grow log. I'll post some pics here just before I start flowering in probably a week or so.


nightcrawler said:
MPL do u have a thread with pics?
 
Some CMH eye candy, for you. we will start with the last pic from 3/13


and then today 3/23, (they were switched to 12/12 on 3/15)


the big plant r00t ball!


Enjoy! :joint:

edit: forgot to say these are from the 4x4 room under 400w CMH. also those of you with keen eyes will see that it is in the 5 gal "holding" bucket in one of the pics, and back in the 3 gal bucket in the other 2 :nono:
 
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simba

Sleeping Dragon
i got 2 of them (lucky find) and i use a HPS and CMH bulb to test ballast, cause im not sure where the cutoff point for the ignitor is on the tester
(as we have found theres different ignitors with ranging outputs)
(i have yet to have a ballast that wont fire stuborn cmh to then try the tester)
IE the tester could test the ballast as good and it still not fire stubborn CMH
But ya those will tell you wich part has failed..
also you can use a Multi-meter and amp meter to check a ballast to.. (not safest for non electricians)
\good find
 
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darthvapor

Active member
I noticed you guys all use the cmh for small grows. How effective would they be if I replaced all 6 of my 1000w hps with 15 400w cmh. Will I get the same density and weight?
 

simba

Sleeping Dragon
IMPHO & IMPHO yes.. you actually may be able to go down to 12 if your lucky..
depending on setup etc.. the main thing no bush's u want mini xmas trees.. and overall yield and potency will go up again impho
the plants on the edges will be allot happier
 
G

Guest

Just wondering if there was an update on when the 600w and 1k versions might become availible.

Is there any difference in the CMH's tolerance to small vibration as associated with a light mover?

Using multiple 400's would probably be a better choice, as having more sourcepoints would be advantageous given the tighter, more compact growth of the plants- making the sheer brute force penetrating capability of the 1k's less relevant.However the cost to retrofit to 400w cores...would be signifcant.I am suddenly jealous of those with 400w ballasts.
 

simba

Sleeping Dragon
heya the arch..
no new word..

nah there fine on light movers..
Honestly 600's and 1kws cmhs will be to much for any grower directly under there plants. its to much also becomes some wasted energy .... (long version shortened)
you would also have to raise the light higher to cover a larger area 400 vs 600 or 1kw and then you have inv sqr law of light against you and thats one of the other big big benifits of cmh. you can go closer cause less heat..
 
Does anyone know how long you have to wait for the cmh bulb to clear custums? Heres what the email from USPS sent:

"Your item left the United States from NJI at 11:00 AM on March 23, 2008. Information, if available, is updated every evening. Please check again later."

That was the second one and most likely the last email update i will get.

Im in need of it badly.... I broke 1 of 2 15W Philips Plant flouros. So now i have only 15W Flouro on 4 9" plants, 3 weeks old.

BTW i live in Canada, major city near Toronto
 

simba

Sleeping Dragon
night i have seen a package from midwest get in to ontario. in 3 total days..
on the other end i have seen it take 12 days.. to get threw.. it really depends on how busy CA post is.. generally always leaves us within 2-3 days.. and then gen takes 2-3 days in ca..


Quote:
Originally Posted by Deft
250Whps vs 250Wcmh
Is there a difference in the overall heat input into a sealed enclosure?
Question for simba.

yes the cmh will not get the room as as hot.. as the hps would.. think of hps like radiant heater (them red glowing ones. that THROW heat at you thats HPS) the cmh arc tube Stops that YA!! (not part of design just a nice sideffect.. )

its kinda penetration.. many of my 1kw users that have gone down to 400s love them.. only one whent back and that was a Personal falling out.. not a issue with the cmh.. (cut his own foot off)
it really comes to effecancy.. ya with 600 or 1kw bushs ok..
its so hard to explain how a single or few cola is better than mass..
allot easier to proses and trim few large colas then popcorn..
 

MPL

Member
I'm finding with my CMH that if you don't keep regular tabs on pruning, you end up with some very, very bushy plants. The tight nodes should produce some really dense nugs though. :)

I have noticed that my 400w CMH runs cooler now that I have it running 20/4 for a couple of months. I am starting to believe there is a 'break-in' period associated with this lamp.
 

simba

Sleeping Dragon
heya mpl glad to hear ur thoughts..
ya thats one of the big reasons i recommending shortening the veg time (that part of the reason ur going to get more growth after the "veg" time..
they get full sun and want to grow more than under hps.. (that full spd is like more food)
not a bad thing at all and with shorter veg that also manages that..

ya there is a break in on them.. listed on the box.. (7)
that it takes time for the color etc to stabilize..
they do however not really show it to us.. or plants. its more like it may jump for a second or two
thats a good thing though.. as threw out its life then it will maintain a 200k+- tolerance (pretty tight) and 85% lumen maintenance..
im also a firm believer that any lamp has a break in period (ie good long cycles on/off vs many short on/off cycles in the beginning will affect life more than at the mid life..and some have chemistry reasons for time to stabilize )
like on HID car headlights they typically go from yellowish to bluer as the hours are put on.. ..

ya heat diff from hps ya..bye bye HPS Bulb AKA radiant Space Heater :wave:
have ya had a harvest yet.. or snagged a nug yet..
 
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G

Guest

Interesting! I'm learning more and more about my 400w cmh everyday. I am vegging for 1 more week and then on to flowering. The plants are bushy like you mentioned. I am LSTing the crap out of them though. Every day I have to tie something new down.

Strains: Purple trainwreck, God bud, Super silver haze, GDP, sour D and Blueberry Kush
 
If iwere to start a new seedling, then place it under the flours for 2 days then under the CMH how long will it need to be under the CMH light untill i...... great.... i lost my thought, dont you hate that...



Yah istill cant think of what iwas trying to say.... maybe something to do with how much bud will i get if its under the cmh pretty much straight from seed..
 
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