Propa Gator
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Not believing and not running the 12 with
If they tried it they'd like it, I did and I do
If they tried it they'd like it, I did and I do
Ceramic Metal Halide vs HPS
- Thread starter OldMedUser
- Start date
NO... CMH bulbs for whatever reason put off less heat.. I don't have the science behind it.. But the back of my hand is all the proof I need....LOL
IMO the only reason some growers would say it's a better veg bulb then a flowering bulb. Is because they are flowering a strain that is mostly bread for an indoor 2k HPS with it and getting poor results. Basically the CMH will flower close to the same thing as the outdoor full spectrum dose. If you have taken your indoor indica strain and grew it outdoors you know exactly what I'm talking about. Poor calyx to leaf ratio. Most indoor strains are not bread to flower under a full spectrum light. Some indoor strains flower just fine under this CMH bulb though..I guess it's all about knowing your strain.
You know, i had long looked into CMH but the fact that it didnt come higher than 400w always made me not take it serious. But theoretically speaking, are you saying that you can order outdoor seeds and flower them under cmh? i always thought of running duel 400w cmh's but let go of the idea for a lumatek altogether lolz
It's been my experience that my indoor sativa dominate strains do better under a CMH bulb then my indoor indica dominate strains do.. Indoor growing for me is all about the calyx to leaf ratio.. Also there are some INDOOR strains that don't flower optimum under (full spectrum lighting) such as sunlight or a 4k (full spectrum) CMH bulb...It's also been my experience that some OUTDOOR strains don't do so well under HID lighting period, and it don't matter if it's a CMH,HPS or a MH bulb..Take my info witch ever way you want to, but that's the best way I know how to answer your question...So I would say no it's not the best idea... You need to test the strain... Sorry
Here's a little graph of the difference between CMH and HPS.
Looks like a good all-rounder for when you wish to view things in a "natural" setting. BUT... How much of that left distribution chart is useful for flowering, I wonder? Those charts aren't listing absolute intensity/lumens numbers, they're showing relative distributions. Assuming that they are relatively equal (the charts, not the bulbs), I would think that those peaks on the HPS chart are indicative of a lot more light than the same wavelengths on the CMH chart. Although I agree that the gross light output would be higher (explaining the less amount of heat output), I am not convinced that it would be more productive for flowering. Not a nay-sayer, mind you, I don't have enough info to form a firm opinion one way or the other.
Will be paying attention in the future. Thanks to all who are experimenting. Would love to see side-by-sides of plants flowered under CMH vs. plants flowered under a few different HPS types. (Would hope that the vegetative phase would leave them equal in all aspects for a true flowering comparison).
It may turn out that the CMH would be the best choice for growers who can only use one light all the way through (like the old adage, if you can only have a HPS or a MH for both cycles, go HPS), but many want to flower under the absolute best light... for flowering.
That mean they came out with something better than Win7 while I wasn't looking, lol? 'Cause up to and including it, it strikes me that all of the "latest and greatest" features were in linux... several distributions back. But I'm diving off-topic.
Have been reading also although I've come late to the party. The skeptic in me wonders what the balance is like after discounting the ones who always speak highly of anything new that they had to pay good money for and also the ones who switched from an old bulb to a new one (that just happens to be a CMH). Seems like a lot of people go WAY too long on their bulb's hours before replacement and that's automatically going to give the nod to the new bulb.
Why I'm glad to see interest here. Google is (not always) my friend, lol, but I know that most here are good for disclosing any results they personally get (both good and bad).
That makes sense not just because of the spread-out light spectrum, but also because of the much higher UV content.
Maybe an equatorial indica would do fine? Something that grows short and stumpy for survival on the harsh windy areas they evolved in, along with the tendency to pile on the crystals for UV protection instead of just going all leafy?
Y'all have got my brain smokin'.
so labrat what are your thoughts on these bulbs after your research. i'm about to build a room and was thinking about 2-400 watters cmh but get mixed reports and some say there the best ever other don't. or a single 600 watt hps on a light rail
If you look at the relative light spectrum of the CMH compared to the HPS, you will see that the red and blue (and most of the the other spectrums) have a much higher percentage in thr CMH. The plants will definitely do better under a 400 watt CMH than a 400 watt HPS. I've found 400 watt HPS ballasts, with a reflector for $130.00. I also found the 400 watt CMH for $42. This means for just ove r$400.00 you could get 2 full systems that would easily outperform a 1000 watt HPS wit only 800 watts, cooler lighting and a better coverage area . Lumens don't really mean anything to plants. Lumens are a measure of visible light. not Infra red or ultraviolet, which the CMH has a ton of. These bulbs are much more efficient!
Great info!
I have a digital ballast for 400w. Can someone please explain why the CMH cannot be use with the digital ballast??
I have a digital ballast for 400w. Can someone please explain why the CMH cannot be use with the digital ballast??
Some hydro store in Seattle states that the adjustable (250, 300, 350, 400) digital GE Ultra-Max ballast will run both CMH and PSMH bulbs.
I also looked at a site that had a big add for the Accendo GloGreen 575-watt (609 watts in) will run the CMHs. I never heard of them before doing a quick search (but that doesn't mean a thing).
Propa Gator
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I use CMH: HPS-Retro White ED18. Philips makes these to replace HPS bulbs in existing factory/commercial fittings. They (Philips) don't seem to care about horticulturists. 250 and 400s only. Other bulb-makers may make CMHs, but I like these. So do my caged plants.
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Yes, but eballasts won't fire them. Old school ballasts are a PIA, CMH are either vert or horizontal specific, and only two sizes available. A 400 CMH lights my veg box right now, but I'll flower them with 600 HPS. Photos in the white light are nice
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I've already chosen digi 600s, but cost is similar and three lamps likely offer better distribution. Similar PAR either way, but I don't like the hot & heavy core/coil ballasts, and hot re-starts don't happen like eballasts do. Accidental or brief storm outages mean 15 min cooling in the dark. Think I'd scale up to k-watts before messing with 400s, but I got very frosty/aromatic weed in a 250 CMH vertical grow. The bulb throws off less waste heat than HPS. Philips CMH are the only HID bulbs safety-rated for open fixtures, but I don't get under my hot grow lights and don't spray any water in there anyway. Water on hot glass is no no.