Ceramic Metal Halide (CMH)

[Guest]

Dragor -

Simba will probably disagree with me and he knows his stuff. That out of the way, let me tell you from my own experience, what I know. When Phillips first released this line of bulbs they did not have a horizontal ready. It took a couple/few years. I ran verticals in the horizontal postion for about 2 - 2 1/2yrs with no known issues. Color may have been off a bit, but not to the naked eye and they probably didn't put out quite as much or for quite as long. I actually called Phillips tech dept and they stated that striking/starting the bulb might be a bit of a bigger load and output might suffer a tad bit. The horizontals look to have more arc tube support.

To cut to the chase, I would not alter my grow set-up or delay things. I would put it in and go for it. As soon as you can afford to order a new Horizontal you should. You could then retire the vertical as a spare or get another ballast and make use of it in some creative way vertically.

Good luck to ya!

Azeotrope

 

[Dragor]

Azeo-
Thanks for your experienced feedback regarding this matter! I was only concerned about the safety of the bulb in the non-standard position - otherwise the wattage is more than enough for my space so a little sacrifice won't matter and the startup can't be THAT much more energy-intensive (although I noticed with the CMH bulb in place, there is a buzz sound to the ballast at start-up for a few seconds before it drops to the normal HPS hum sound, this is normal I assume?). In any case, things looks great the light is INTENSE and the temperatures aren't difficult to maintain, excellent investment it seems and I plan to use it the first half of flowering to mimic summer then pop in the HPS to finish them off.. will post pics of my babies/cab soon...

edit: photo added below, such a nicer light spectrum & more natural photo shots

 

[Guest]

Looks like you are off to a good start!! I might suggest that you just run the CMH the whole way through. Especially in the last 3wks when the blue and UV output of the CMH will help them resin/harden up. Much better than the HPS.

 

[Dragor]

Looks like you are off to a good start!! I might suggest that you just run the CMH the whole way through. Especially in the last 3wks when the blue and UV output of the CMH will help them resin/harden up. Much better than the HPS.

Oh nice advice Azeo and thanks for the compliments on the new change, took your advice on horizontal mounting of the V bulb
I have definitely heard and read the proof of UVB helping with resin secretion during late flowering but I guess there's no point in trying to mimick nature and give just red light when naturally there should be ALL wavelengths of light in the daytime regardless, just at less intensity towards end of growth so I can simply raise the light up higher accordingly at the end of flowering. I am excited about keeping my ladies much shorter and stockier now with this light as I can't afford much height as you can see plus I am doing topped plants that will be tied into bundles of tops at low height. Thanks again for your advice, other's help would be great too,
peace...

 

[greenisgold]

If you can, get the plants/pots closer to each other and towards the middle of the hood, or put that one plant on the far left in the middle.

 

[Guest]

Yes, Pulling the light up can be a good move at the end.

 

[Guest]

Flowering under the CMH progress report. Around day 31/32 12/12. Willijuana in the middle and JohnnyBlaze on the sides. Also the little AsiaGirlXNl5Haze has recovered and should yield a little befrore another re-veg.

 

[Dragor]

So Azeo from the pics you are showing that the HPS light is brought down closer to the flowering tops than your CMH reflector/setup? I noticed a couple of my plants (the more indica dominant ones) are starting to curl at the tips of the leaves and they are drooping when they are well fed with water (not overwatered either). My temperatures went up by 3-4 degrees F since the change to CMH from HPS. I even have my ballast remote and the temps inside are barely staying around 80.

 

[Guest]

I don't have an HPS bulb burning, just a questionable camera that rendered one pic kinda orange? That CMH is about 4" - 6" off of the canopy as referenced by the small trimming shears. It is a matter of fact that the smaller ceramic arc tube of the CMH contributes less total heat than the HPS and that it comes out differently. That is 2x400w in 22"X40" cabintet! No temp problems except 90+F ambients in the summerLOL

 

[chimei]

So I finished my first full flower with the Philips 400 Watt CMH bulb.

I like it, I wound up with what I normally would pull off of a plant of the size I vegged, since I have not grown this strain before I can't tell 100% the difference.

And I don't really feel like doing a side by side.

All bud sites were rock hard dense, even the sites that were further away. (I did not do ANY LST) My first flower I wanted to see what would happen. I will be going back to LST next grow.

I did find a few pollen sacks after I started trimming. I am sure that must just be this plant. I did not stress her at all other then some low 60 degree temps, this was a bog medley plant.. not sure which one possibly an LSD given its nasty smell and what I have read on some grow reports with that strain. (Natural gas + dead fish is what I got at the end when handled or smelled, then after that dissapates from touching.. fingers smell really fruity like skittles)

It also could just be the strain, but it was also the smelliest grow I have ever had, even with just one plant it was amazing how overpowering it was.

I am very happy that I can stick with one bulb and in each cycle it is getting more of the light spectrum in either phase then running MH in Veg and HPS in flowering like I always had done.

Here is a pic 5 days before I cut her down.

 

[bigdaredevil418]

some seeds....some dirt.....some water.....some love.......why does it have to be so hard ??? I am very motivated...dont get me wrong...It's just overwhelming sometimes
Thanks
bdd

 

[Guest]

.......some sun........ That's all we're doing isn't it!

 

[Dragor]

Hey Azeo:
I am really starting to get worried about the change to CMH...
About 24 hours after putting them under the new light (from previous CFL cab) the leaves changed texture from soft and pliable to tough and course and have curled down and inwards... Not a natural look, like they are getting toasted almost...
The temperatures have been somewhat higher than normal at mid to upper 80s today, and about 80-85 otherwise. I started off with the light at 10" away (with fan blowing across the bulb) then moved to 12" and now 15" and there's still not been a significant change back to normal plant health... I need to know if anybody else experiences these initial types of "shock" to their plants under CMH? Too much UV radiation? Please help I am confused, thanks... I am considering going back to HPS for flowering as that should be starting sometime very soon...

Here's a link showing my plants' conditions:
http://www.icmag.com/ic/showthread.php?p=1463880#post1463880

Hope somebody can give some sound advice about this... thanks in advance!

 

[Guest]

I have seen HPS plants suffer from UV shock when going outside. I don't know what you are seeing, could be just that. I have never had a sick plant under the cmh (other than neglected or abused due to experiment!lol).

Just looked at the pics. I'm thinking on it. Doesn't look like a light thing though. Could anything else be different? Humidity?

 

[simba]

Im a lil behind on all so ill be short...

Hey Azeo:
(from previous CFL cab) the leaves changed texture from soft and pliable to tough and course and have curled down and inwards... Not a natural look, like they are getting toasted almost...

Why yes infact they are being "burned" (notice the quotes)...
they where under CFL which is a soft light (non HID)
and they grew to there environment they didnt need to be ridged to hold more mostier as its not leaving as fast (just one example and to give u idea)
and all of a sudden "shocked" with HID (FULL SPD HID IKES)
and in a hurry tried to thicken its walls etc and turned UCK (shortened version)

think of it this way.. you never do any manual labor..or allways where shoes and have soft feet.. and then you DROPED in the wild your feet and hands will have trauma and rebuild kinda fast and uckyy..

sorry if this dont make sense im so behind and this is the simplest way i can explain it..

HOwever this is not to say this is normal.. and i know CHit about perlite/soil but it can happen to plants when you go low light and very "soft enviroment" to HARSH (cfl to HID) (where not talking babies/clones rather plants mid to late veg /flower switch )


Dont go back to CFL your plant will really shock and who knows.. it will do beter requiping here than going back..

dont get me wrong i like certin Flor's but they have there place..

 

[NoSayHombre]

When switching from a weaker light source (cfl) to a stronger (cmh), it would seem prudent to start with the light higher than you think it needs to be and gradually bring it down over 3-4 days. It is much easier to recover from light shortage than from a burn.

I have switched all my lights to CMH and lovin it.

 

[Dragor]

Azeotrope, Simba & NoSayHombre grateful thanks to you guys for the excellent words of wisdom on how to transition/adjust to CMH, I just wish I had consulted you guys before I dove head first into this crazy new deal... aye! I just raised the light further more to about 20inches away now and have 2 fans in motion, one blowing across bulb and the other oscillating the rest of the air in the cab...

They are looking somewhat better but I wonder if they will ever revert back to healthy or only new growth will pick up health? I am considering flipping to 12hrs tomorrow night because they are all about 7-12inches and will probably stretch to 20-30inches final height (barely fitting in my 28" available plant space). I wonder if I should just keep the light this far away for the rest of the time, as I don't want to risk lowering it again. I think there's SO MUCH quality light that it can be almost 2 ft from the tops and not cause stretching (as HPS would) ... what do you guys think?

I am totally stoked about this bulb/technology and don't want to give up on it just yet, I know it holds mad potential... I just have to make some op adjustments: get the cab even cooler, below 80F ideally... I'll update you guys in the next day or two... Peace UP! thx again

 

[NoSayHombre]

Geez...28 inches. You for sure don't want to go back to hps. Your plants will stretch less with the cmh. If/when things start looking normal again, you might want to try lowering the light about an inch a day. Don't go too much overboard with fans on the plants. Too much airflow can dry out the leaves, too.

 

[chimei]

That could be pretty stressful, they were under CFL's then you moved them under a CMH with fans?

I stopped running fans years ago, where I am at the RH level is low so fans do more harm then good.

I use a hood that has a fan pulling the hot air out of it.

In my case I move my young ones that came from CFL under my light (MH/CMH/HPS) and start at like 3.5 feet away for the first 2 days then move a foot closer each day after until I am where I want to be.

 

[chimei]

I also have to add after finishing my first flower with CMH, I would have to say after drying for a bit now that this plant seems to have more oil in the buds then usual. I won't know till I run another strain if the light had an effect on that.

I will know after my cure, I like bud that can stay nice and sticky.