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Gavita DE vs. CMH 630w systems: pros and cons of both?

timmur

Member
luxcultivars for what it's worth from another forum:
Ive wondered about the difference between sun systems single vertical and dual horizontal reflectors performance wise.I have a friend whos using Lecs and dual dpaps and much prefers the single Lecs to the dual dpaps.

Why does he prefer the singles?

He thinks he gets better coverage from the Lecs,not sure if its the reflector and vert bulb or what,ill ask him hes coming up for lunch today.

And this as well:
315 Philips Master Color Elite Agro driven by Boulder Light ballast for the win. We were averaging 1.3lb/1000w we replaced each hood with 2.5 fixtures, ie 4x8 table has 5 in a row. We are now seeing an average of 2.3lb for the equivalent space, changing nothing but the light. Approximately .93lb per fixture, and I dont believe for a moment that we have maximized the potential.

Finally this:
I've got 12 SS LEC's and I love them I also have some dpaps but I like the LEC better, I'm looking to expand the veg room and just wanted to make the right purchase. I've been paying 375 out the door for the LEC 315s.
 

Jhhnn

Active member
Veteran
My point was this: if you can't see the difference on the scale at the end, how are you quantifying the fact that the plant is worse off and 'compensating'?

Anyway, I think we're all on the same page in wanting more usable spectrum from our wattage inputs. Thanks for the input.

In the weighing, you haven't compared any of the light sources to CDM but rather to each other. That needs to be done before reaching any conclusions about yield.
 

bluerock

Member
Hey timmur,

I'm the one that consulted Cycloptics and the grower on that grow test, to setup and use the Greenbeams fixtures (e.g. in terms of goal PPF, room setup, etc.), and I also hung much of the ORCA on those walls in the pictures ;). The funny thing is the grower didn't use the GB correctly to plan, and had they, the results would have been even better.

Greenbeams would also beat Gavita or ePapillion, assuming ideal PPF at canopy was used for all rooms, simply due to the better spectrum from the Philips CMH and uniformity of PPF at canopy from Greenbeams. In these cases, penetration isn't an issue due to the many fixtures per room.

The only downside about Greenabeams, or any 315w system as luxcultivar pointed out, is the start-up cost.

Regarding the PDF file cited in post #52, it has several flaws and can hardly be called "scientific". I'll get to those, but firstly I would ask what you mean by "consulted Cycloptics". Were you paid by Cycloptics for this consulting? It's a fair question.

As to the PDF, the immediately apparent flaws are:

1. Based on the manufacturer identification data on the last page - basically an advertisement - this is obviously a manufacturer sponsored "test". Really, that ought to discredit it right there.

2. The purpose of the test was to do a comparison of Cycloptics products to the lighting regime typically used by the grower per the document. Well, the lighting "regime" used by the grower is questionable, particularly the 600w MH.

3. I note that the data for the Cycloptics product does not break out the number for days used for veg/flower, whereby the "testers" do state such data for the MH/HPS setup. Although I think that a 600 MH would be sub-par for such an effort, the "60 days veg", that would typically produce some large plants going into flowering.

This "comparison" isn't even really worth any further consideration based on the flawed methodology, manufacturer bias, and generally insufficient data. For example, what would have been the result had they vegged with the HPS? Quite different, I am sure.

Beta, you surely don't consider that "comparison test" as anything other than a product brochure for Cycloptics?
 

bluerock

Member
Correction to point #3: They are claiming 73 days at 13 hours light for the Cycloptics. Still, my objections stand: this is a badly flawed "comparison test". 13 extra days in flower makes a big difference. I also see that the last day Cycloptics plant photos feature yellow fan leaves from top to bottom. Not that I think that is being caused by the lighting, but perhaps an overzealous nutrient program. There are no photos of the HPS plants. That is to be expected, considering the sponsor.
 

bluerock

Member
Of course they don't have any photos: that document does not feature an active comparison test. They are comparing the reported past results of the grower. Ridiculous.
 
Regarding the PDF file cited in post #52, it has several flaws and can hardly be called "scientific". I'll get to those, but firstly I would ask what you mean by "consulted Cycloptics". Were you paid by Cycloptics for this consulting? It's a fair question.
Well it's good you don't think it can be called scientific, because no one called it scientific ;)

No I was no paid by Cycloptics. I did it as a favor to a friend.


As to the PDF, the immediately apparent flaws are:

1. Based on the manufacturer identification data on the last page - basically an advertisement - this is obviously a manufacturer sponsored "test". Really, that ought to discredit it right there.
No it's not sponsored. The test was independent, by a grower who didn't believe in Greenbeams and didn't want to do the testing (but who's employer wanted to test them out). The grower was happy with 1000W HPS and thought Greenbeams was a waste of time. (Of course, that's before he started using them.) The company that did the test purchased all the units for the test.

2. The purpose of the test was to do a comparison of Cycloptics products to the lighting regime typically used by the grower per the document. Well, the lighting "regime" used by the grower is questionable, particularly the 600w MH.
Your point is?

Many growers use less than ideal lighting, this was a real world test to compare a pretty typical grow to Greenbeams.

And like I wrote on the last page, if this test was done vs. Gavita or ePapillion, Greenbeams would still do better (e.g. if the PPF was the same for all test rooms, which would be a good way to compare them). This is basic logic. But I'm sure you won't agree, you'll just fall back to your talking points.

3. I note that the data for the Cycloptics product does not break out the number for days used for veg/flower, whereby the "testers" do state such data for the MH/HPS setup. Although I think that a 600 MH would be sub-par for such an effort, the "60 days veg", that would typically produce some large plants going into flowering.
Not sure what you're driving at here.

This "comparison" isn't even really worth any further consideration based on the flawed methodology, manufacturer bias, and generally insufficient data. For example, what would have been the result had they vegged with the HPS? Quite different, I am sure.
Great! Then don't consider it anymore :)

Beta, you surely don't consider that "comparison test" as anything other than a product brochure for Cycloptics?
See above.

And no, it's not a scientific study, that's why no one claimed it was, and yes, it was not designed to compare optimal usage of all luminaires, it was designed to compare common real-world grow to usage of Greenbeams.

That commercial grower who did that test grew with HPS and MH in the way described for years, it's not like Cycloptics asked them to setup the luminaires like that.
 
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Of course they don't have any photos: that document does not feature an active comparison test. They are comparing the reported past results of the grower. Ridiculous.


It doesn't matter that they compared past grow to a grow with Greenbeams. The results would be the same if both grows were concurrent.
 

bluerock

Member
It doesn't matter that they compared past grow to a grow with Greenbeams. The results would be the same if both grows were concurrent.

Ah, science by extrapolation. That's always valid. The "grower" in the advertisement is clearly interested in producing commercial quantities of product. And yet, he supposedly used a 60 day veg time from clones while only flowering for another 60 days.

In contrast, the CMH were not vegged at all but flowered for 73 days. While 73 days is quite a while, that process is more in line with what the typical commercial grower actually does. Little (say max 21 days) or no veg time.
 
Hi BTT - still really curious about the height and spacing of those Greenbeams in the test...? They seem really high up there (8'?) to have enough light penetration? Are those final yield numbers really based upon 315s hung at 8' height? Also, a 30" spread?

--------

Timmur - thanks for posting that. Sounds promising. I am still wondering, though, how two 315w fixtures' output could be so much better than a 630w double fixture that it somehow justifies spending the extra $300 for those two fixtures instead of one 630. Not getting that part at all. I can see clearly that multiple 315s is obviously a better way to do it, no doubt there, but the cost difference is seriously prohibitive. Again: $550-600 for a 315; ~$700 for a 630 double...

I suppose I could go for Sun System's 315w vertical-bulb fixture (I could get them for about $450), but their ballast doesn't have the dimming option. Think I need to insist on that feature at these prices.

Why exactly are these fixtures so much more expensive than conventional HID lighting? Are the parts/ballast more costly? The bulbs are even cheaper. Is this just gouging?
 
Bluerock, did you have something to actually contribute to this thread or are you just here to pick fights with BTT? Your constant attitude-dishing is getting pretty tiresome. Would you like to run some tests for us? Since BTT's work isn't up to your standards and all? We'd all appreciate that hands-on contribution. Thanks, man.
 

bluerock

Member
Bluerock, did you have something to actually contribute to this thread or are you just here to pick fights with BTT? Your constant attitude-dishing is getting pretty tiresome. Would you like to run some tests for us? Since BTT's work isn't up to your standards and all? We'd all appreciate that hands-on contribution. Thanks, man.
I'm not here to pick fights at all. Beta is a professional scientist and it looked to me like he was endorsing what is basically an advertisement by the manufacturer featuring what could charitably be called hearsay evidence. As you have noted, these systems are expensive. I know several people that bought into the LED hype and wound up with a bunch of overpriced fixtures they no longer use and have been unable to liquidate.

Your thoughts regarding "why are these so expensive" have been on my mind as well. Looking forward to some answers.
 

iBogart

Active member
Veteran
This sounds like pure speculation, not science. How do you figure that they are 'compensating'? I'm seeing explosive flowering and growth, not compensation.

It is also a lot more complicated than 'they need more blue'. I think BTT was trying to show you that. Reducing things to their simplest form isn't always the best approach. In this case too much detail is lost in that translation.

When it comes to measuring actual plant performance and achieving the true genetic potential of various hybrids and strains (something I strive towards and usually achieve), your 'more blue' theory doesn't hold up. For example, I have grown and flowered cannabis several times under conventional metal halides with plenty of blue (6500k), and also under Eye-Hortilux HPS. The HPS definitely brings in the higher yields with ease. Quality seems superior as well, subjective as that is. Why would this be so if your theory is even vaguely correct?

I'm not anti-blue so much as of the mind that designing lights that specifically output only the spectrums that plants actually use - be that warm or cool or preferably some of both - rather than wasting electricity generating photons that have no use to the plant. That is just extra heat.

This is what got me leaning towards the CMH, actually; the targeted horticultural spectrum.

I wouldn't say targeted, more like broad. The plant is going to prefer different wavelengths through the different stages of growth. Nothing new here. You're covering all you bases with CMH. You'd be covering your bases, and targeting your spectrum by using a lamp thats designed for vegetation, and one designing for flowering. I guess the thinking would be why waste the photons if the plant is not needing it? As you know, that's why you get nice green leaves and tight internodes with a light with blue spectrum emphasis during vegetative stage, and higher yielding plants with lights with red spectrum emphasis during flowering. Again, we all know this. There's not just one path to success. I can grow super happy go lucky plants during their vegetative stage with T5's all day long, 365 days a year. And grow super fat sticky nugs under HPS during flowering. The big question is, how much of a difference that method produces compared to growing with a CMH all the way through? I think it'll be damn close. I'm sure we agree on this as well. It all comes down to your particular setup/growing environment/growing method that should determine your best lighting choice.
 

Jhhnn

Active member
Veteran
I'm not here to pick fights at all. Beta is a professional scientist and it looked to me like he was endorsing what is basically an advertisement by the manufacturer featuring what could charitably be called hearsay evidence. As you have noted, these systems are expensive. I know several people that bought into the LED hype and wound up with a bunch of overpriced fixtures they no longer use and have been unable to liquidate.

Your thoughts regarding "why are these so expensive" have been on my mind as well. Looking forward to some answers.

LED grow lights as we know them are not the result of a major engineering effort by one of the world's leaders in lighting technology.

Quite the contrary. LED grow lights have been built around fast buck marketing, at least AFAICT. Never used them, likely never will.

The reason that CDM is expensive is because it's really cutting edge industrial technology, not intended for us at all but rather for parking lots & large commercial spaces. It's the kind of stuff where the fixtures & Philips ballasts are intended to be neglected for 20 years & the lamps changed every few years, maybe. Don't have to fuck with it high technology. The engineering effort has been huge, the price of the components in their CDM ballasts well on the high side. Creating low frequency square wave high power drivers isn't an easy task at all.

Old style core & coil ballasts are built the same way- good ones, anyway. They're cheap because the tech is simple & demand huge. Growers' electronic ballasts aren't built for that but rather built to be disposable in a few years. Anything that uses a 3 cent fan for cooling is cheap stuff, ya know? You won't find them in industrial highbay fixtures unless they were specc'ed by idiots.

Philips isn't after our grubby little cannabis cultivator's market at all. Hell, they recently prohibited their distributors like cycloptics from dealing directly with growers, if that tells you anything. They maintain the illusion that their DE series is aimed to be supplemental lighting for huge greenhouses full of petunia starts, but they realize that CDM isn't really practical for that purpose.

It all comes back around to what I offered to Beta. What's the best light for plants? The visible portion of natural sunlight, same as for human eyesight. What light approaches that most closely? CDM, at considerably higher efficiency than all but the frequency limifed DE lamps.

Hell, growers pay $250/lamp for EYE horilux dual arc lamps that do the same thing at lower efficiency & half the lamp life.

http://eyehortilux.com/products/htl-dual-arc/PerformanceSpecs/lu1000mhhtlen/62800
 
I wouldn't say targeted, more like broad. The plant is going to prefer different wavelengths through the different stages of growth. Nothing new here. You're covering all you bases with CMH. You'd be covering your bases, and targeting your spectrum by using a lamp thats designed for vegetation, and one designing for flowering. I guess the thinking would be why waste the photons if the plant is not needing it?

Because CMH does both at 2/3 the power consumption and 2/3 the heat output of either conventional MH or HPS. That's a pretty compelling reason IMO if performance is the same. Add to that the gradual decrease in output of conventional HID bulbs; my HPS EyeHortis are only at around 75% output after 9 months (or so my light meter usually tells me). That's a pretty significant loss. So, $90 twice a year per fixture to keep full output. Halides are even worse. CMH bulbs maintain life and output considerably longer.

I can grow super happy go lucky plants during their vegetative stage with T5's all day long, 365 days a year. And grow super fat sticky nugs under HPS during flowering. The big question is, how much of a difference that method produces compared to growing with a CMH all the way through? I think it'll be damn close.

You nailed it. I think so, too, and all reports seem to indicate that as well. And if that's really the case I'd definitely make the initially-higher-cost investment. At this point I'm hoping for either verifying tests or performance reports I guess.

The ability to use a room for both veg and flower is a huge draw for me. I keep a tight schedule and often have to veg for a few days longer under HPS if the veg area gets backed up. Sometimes the opposite happens and I begin flowering under 6,500k MH. Probably not a huge difference, but still.
 

timmur

Member
@luxcultivars

From another site addressing the distance from canopy question (though referring to the Sun Systems LEC rather than Greenbeams):
I'm currently running 36x Sun Systems LEC 630W 4100k for my Veg room.
I feel that they work extremely well, although I have to keep them a good distance from the plant because if you bring them down close to even 3 feet away from the canopy you will see light burn, I keep them 4-5 feet away and the plants seem to have vigorous growth, a complex root system and much thicker stalks and branches.. doesn't even compare to other lights.

Not my photo, BTW.
 
Good points, Jhhnn. Although aren't the greenpower bulbs specifically designed for horticultural use? Regardless, I'd like to hope the costs will come down but knowing the industry, I doubt it. Although with a new legal cannabis reality coming up these companies are definitely going to take a second look at where the money actually lies.

Speaking of LEDs, I looked heavily into that option and decided the fixture-to-canopy close proximity requirement bugged me too much. I hate raising and lowering lights. I prefer at least 24" from fixture to canopy, and the penetration of LED frankly sucks IMO.

That said, the COB LEDs are a very interesting technology. I've played around with a few 50w COB spotlight fixtures and they can be useful in areas where steady growth isn't the focus. IOW, for isolation/quarantine areas, for large mothers or for any plants that you want to slow down. I have a large library of cultivars so this can be helpful. I mainly use T5s but they can get warm. And the bulbs get expensive.

I also just used two 50w COB warm spots over a reversed 'The White' plant and it threw pollen very well. It isn't HPS intensity, but I concluded that four of these over a 36" x 36" area would be a very nice breeding chamber. They run cool, they only cost $40 each, and only burn 200 watts.

They make great work area lights too. That's pretty much why I initially bought a few.
 
@luxcultivars

From another site addressing the distance from canopy question (though referring to the Sun Systems LEC rather than Greenbeams):

Wow, Timmur, that's actually great news for me. I have 8' ceilings, so I'd do okay. But this is a very important detail for anyone considering these: I've heard a few reports of burning with CMH now. Anyone with limited height is not going to want to go this route.

There's another thing to consider: a ballast like the DimLux 630w CMH has 7 different dimming levels. You could run your fixtures at 85% if necessary. I'm curious: do the plants eventually adjust to the intensity? IOW, should they be hardened off first by gradually increasing output? Or do they burn no matter what stage?

Maybe this is why the 315w fixtures are preferred; more distribution of the light likely results in less or no burning.
 

bluerock

Member
The reason that CDM is expensive is because it's really cutting edge industrial technology, not intended for us at all but rather for parking lots & large commercial spaces. It's the kind of stuff where the fixtures & Philips ballasts are intended to be neglected for 20 years & the lamps changed every few years, maybe. Don't have to fuck with it high technology. The engineering effort has been huge, the price of the components in their CDM ballasts well on the high side. Creating low frequency square wave high power drivers isn't an easy task at all.

Old style core & coil ballasts are built the same way- good ones, anyway. They're cheap because the tech is simple & demand huge. Growers' electronic ballasts aren't built for that but rather built to be disposable in a few years. Anything that uses a 3 cent fan for cooling is cheap stuff, ya know? You won't find them in industrial highbay fixtures unless they were specc'ed by idiots.

Philips isn't after our grubby little cannabis cultivator's market at all. Hell, they recently prohibited their distributors like cycloptics from dealing directly with growers, if that tells you anything. They maintain the illusion that their DE series is aimed to be supplemental lighting for huge greenhouses full of petunia starts, but they realize that CDM isn't really practical for that purpose.

It all comes back around to what I offered to Beta. What's the best light for plants? The visible portion of natural sunlight, same as for human eyesight. What light approaches that most closely? CDM, at considerably higher efficiency than all but the frequency limifed DE lamps.

Hell, growers pay $250/lamp for EYE horilux dual arc lamps that do the same thing at lower efficiency & half the lamp life.

http://eyehortilux.com/products/htl-dual-arc/PerformanceSpecs/lu1000mhhtlen/62800

A few points: CMH is not new. The idea for the higher wattage bulbs was that they could replace MH/HPS in factories and offer more "natural" light. I've never seen one in an industrial factory, and I have visited many of them. Indeed, VHO T5 seems to be the choice for upgrading such facilities to more "natural" lighting.

Why do you think creating a low frequency square wave ballast is a technical challenge? It is my understanding that the reason Hortilux went this route for their 1000w HPS is because they couldn't get digital right. Hortilux has yet to offer a DE bulb.

The ballast life advertised on 208-240v CMH ballast from Phillips is a mere 50,000 hours. A little less than 6 years at round-the-clock usage. That's hardly a marvel of electrical engineering.
 
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