HPS, MH, Floros, Phillips Cermamic Metal Halide has 'em all beat.
- Thread starter ThatOneDude
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DR. VonDankenstine
Well-Known Member
Thanks for the info/post, and opinions on the light---I hope it works out for you----as far as jumping on the "next best thing" a lot more testing needs to be done---a lot of factors to consider---You should do some side by side tests and really see what the facts are. Could be great--------could be a fart in the wind. Thank you again and best of luck with your research.Greetings fellow weed growers and lovers! I'm new here but not new to other forums. I've seen a ton of noobs asking about lighting and all anyone has to say is HPS, MH, Floro or LED. Time to stir some shit up and help some of you out and get you out of the dark ages.
LEDs won't be refined for a couple of years, I've seen grows fail, I tried them myself as supplemental lighting, and for clones. To say the least, I wasn't impressed. They need work, they may be the best thing out there at some point but for now, you're better off with floros in my opinion.
HPS lights are great for flowering and for you noobs out there, YES you can veg under them too! Every post about lighting here seems to tell people that you NEED MH for vegging and HPS for flowering, THEY ARE WRONG! I've had grows with just MH. While HPS is better for flowering, But there is something better then both of those bulb even if you pay the jacked up price for the "super duper specially enhanced king of all" version of either of those bulbs.
Forget all of those OVERPRICED "enhanced" horticulture bulb for both MH and HPS. People get hung up on how many watts and how many Lumens without understanding what they are for. It's advertising, it's sales, it's all about exaggerating something and making it seem more important than what they can be used as. The news does the same thing every night, exaggerates the story to get viewers to increase sales. I'll let you know now, I'll put a 400 watt CMH bulb up against their 600 watt "enhanced bulb" and embarrass them all, as for a 400 watt enhanced bulb it doesn't even come close.
Take a look at the comparison on the light spectrum chart, it doesn't take a expert to see the difference.
All of that and check out the second picture....... yeah, that bulb is lit and being held. The bulbs run that much cooler then HPS and MH bulbs. No air cooling hood needed! most of the heat goes vertical on the bulbs.
And check out the pics of the grows. As you see, they are different grows, the bulb is proven.
These bulbs run about $50
They work on standard HPS ballasts of the same wattage
They run much cooler which put them closer to the plants and makes them much more effective.
They range in watts up to 400 watts. there is no 600 or 1000 watt out there right now but they are coming.
Not for digital ballasts, they require a hard strike to fire up.
There's endless advantages to these bulbs.
Got Questions? Comments? Sarcasm? Hit me with it.
ceestyle
Well-Known Member
That's funny, I seem to see that MH conversions get about 36-37k , compared to 39 quoted with the CMH. Considering the amount of useless or overweighted spectrum with the CMH, you're probably getting more useful light with the MH.
In any case, is your argument really that CMH is the "revolution" because you think it's slightly better for veg and runs cooler? Come on, what we care about it harvest. Why else would people run HPS through veg and flower, rather than MH ? Flowering period is obvously the most important lightwise.
ceestyle, you must be stoned, or don't know how to read, your link shows the MH lamp STARTS at 32,000 in the horizontal position, but due to lumen degradation goes downhill fast. I've tried a conversion lamp, and the plant just goes yellow and shrivels up.
there is no useless spectrum on a CMH, just compare to the photosynthesis action spectrum, and it's a perfect match.
there is no useless spectrum on a CMH, just compare to the photosynthesis action spectrum, and it's a perfect match.
ceestyle
Well-Known Member
First of all, it's simple enough to respond without being a dick. I clearly stated that I am not an expert on CMH.
I'm interested to see that CMH has better lifetime / degradation than a MH. From what I've seen, they have comparable lifetimes. If you have some to compare for CMH, I'd be interested to see it.
Your anecdotal evidence is just that. I'm sure there are many with good luck with conversion lamps - such as myself - that would beg to differ with your opinion of them.
Without getting back into the details of the CMH argument I've already made - which you may feel free to read - we know that the HPS spectrum is best for flowering pot. Period. Until you show me a side-by-side that shows otherwise, I'm going to go with the science and vast documentation of the efficiency of maximum red/yellow spectrum for flowering.
If you're still debating what is best for vegetative growth, I would still ask to see proof of that, but would add that I don't really care that much. People still veg with fluoros, for chrissake, but nobody skimps on the HPS who wants the best results..
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Ceramic metal halide has an extremely shallow lumen degradation, has excellent maintained lumens. Also CMH has loads of red. What I am talking about is optimizing, because obviously when the plants are small, they just can't physically use all the photons from a 58,000 lumen 400w lamp, but what we are not taking into account, is that HPS is very high in lumens AS AN ARTEFACT OF HOW LUMENS ARE MEASURED, which is green and yellow photons are weighted very high, whereas blue and red photons, to which THE EYE is less sensitive to, BUT CHLOROPHYLL IS MORE SENSITIVE TO, means that TOTAL PHOTONS, is probably very similar. Remember, how a CMH lamp is made: they just take an HPS lamp, and SPIKE IT WITH RARE METALS, to make it give off lots more blue and red, which IS PERFECT FOR WHAT WE WANT AS POTGROWERS!!! Peace, and sorry to be a dick on my last comment, but you posted the completely wrong lumens.
ceestyle
Well-Known Member
It seems to me from this spectrum that CMH is much heavier on green and the colors that lumens are weighted to more heavily than HPS is. Compare those to the luminosity function, and you'll see that the maximum of the black curve is centered in a region (~550nm) where the CMH spectrum is heavy and flat. I think you'd have to work the math out on that to say anything, which means it's not a trivial point.
You still have not provided any data that shows this slower degradation, or higher lumen count. I understand that lumens are based on human sensitivity, but until you convert to PAR, you have to deal with the argument above.Considering again that red and yellow have proven to do what we want in flowering, and that HPS still has more red and yellow, it is still a better flowering bulb.
Perhaps it would help if you clarified your argument: are you saying you think that CMH are better than HPS for flowering? Are you saying their better than MH for vegetative growth? Or both?
ceestyle
Well-Known Member
proving what?
BigBudBalls
Well-Known Member
Rent it. (damn 10 char lower limit)
ceestyle
Well-Known Member
you can convert all the spectra using software i have ... but it would be a huge PIA for little end benefit. If I had any interest in CMH, I might consider it.
ceestyle
Well-Known Member
BTW - for the record, the Retro-white stats are given for the vertical, base-up position, so the stats are comparable. You must be stoned too. Apparently if you're reading this ... well, you can read.
Really google is your friend.
Where you need to go is google on converting spectrum to lumens.
There is one curve for plant lumens, and another curve for human lumens. The lumens given by the manufacturer of the lamp is for humans. But there is a HUGE difference between plant and human lumens, so the only way to find out the number, is to take the measured spectrum, and then do the mathematical thing called multiply the curve by the normalized chart. This is given on the following site. As you can see, Towards a Plant Growth Lumen
shows the following chart:
Spectral Factors
nm lumen plant
350 .000 .041
360 .000 .047
370 .000 .056
380 .000 .071
390 .000 .098
400 .000 .134
410 .001 .165
420 .004 .198
430 .011 .222
440 .023 .232
450 .038 .212
460 .060 .198
470 .091 .201
480 .139 .212
490 .210 .224
500 .326 .237
510 .504 .241
520 .706 .242
530 .859 .248
540 .951 .263
550 .993 .289
560 .993 .313
570 .950 .340
580 .868 .369
590 .756 .397
600 .630 .420
610 .503 .443
620 .380 .461
630 .266 .476
640 .175 .493
650 .108 .509
660 .061 .523
670 .032 .535
680 .017 .525
690 .008 .421
700 .004 .273
710 .002 .122
720 .001 .081
730 .000 .062
740 .000 .046
Wavelengths between 420 and 500 are worth about 0.2, then the "plant value" rises rapidly to close to almost .500 at about 640, and then at 690 starts to really drop. Notice that CMH has a lot of its spectrum in the short wavelength, which doesn't count for much, but also has quite a bit in the far red, more than HPS does, which counts as more. However, the spectrum is for a PHILLIPS lamp with a color temperature of 4000K, but GE also makes a better CMH than PHILLIPS, it costs close to $100, but lasts longer and has a lower color temperature of 3000K. I would like to compare the GE lamp to the Phillips lamp for spectrum, but GE doesn't publish it; since the GE CMH is 3000K, it will even be more rich in the far reds and may even start to be as good as an HPS for plant-lumens/watt. Basically, the bottom line is that it is not possible to beat HPS, HPS has them all beat, but for the early growing periods, like the first half of the grow, I would use a GE CMH because of the beneficial effect on PLANT MORPHOLOGY, setting up the basic structure and skeleton of the plant, is better with CMH. Or you could use a pulse start metal halide for the first half of the grow, which would be just as good, since the blue component is important in the formative stages of plant growth. Towards the end we are just "fattening up" the plant, with piles of THC, just like a farmer fattens up the cattle, after they have had their mother's milk during the first part of their lives. The CMH is like mother's milk, and the HPS is like the grain feedlot. Peace, Sativa.
750 .000 .032
Where you need to go is google on converting spectrum to lumens.
There is one curve for plant lumens, and another curve for human lumens. The lumens given by the manufacturer of the lamp is for humans. But there is a HUGE difference between plant and human lumens, so the only way to find out the number, is to take the measured spectrum, and then do the mathematical thing called multiply the curve by the normalized chart. This is given on the following site. As you can see, Towards a Plant Growth Lumen
shows the following chart:
Spectral Factors
nm lumen plant
350 .000 .041
360 .000 .047
370 .000 .056
380 .000 .071
390 .000 .098
400 .000 .134
410 .001 .165
420 .004 .198
430 .011 .222
440 .023 .232
450 .038 .212
460 .060 .198
470 .091 .201
480 .139 .212
490 .210 .224
500 .326 .237
510 .504 .241
520 .706 .242
530 .859 .248
540 .951 .263
550 .993 .289
560 .993 .313
570 .950 .340
580 .868 .369
590 .756 .397
600 .630 .420
610 .503 .443
620 .380 .461
630 .266 .476
640 .175 .493
650 .108 .509
660 .061 .523
670 .032 .535
680 .017 .525
690 .008 .421
700 .004 .273
710 .002 .122
720 .001 .081
730 .000 .062
740 .000 .046
Wavelengths between 420 and 500 are worth about 0.2, then the "plant value" rises rapidly to close to almost .500 at about 640, and then at 690 starts to really drop. Notice that CMH has a lot of its spectrum in the short wavelength, which doesn't count for much, but also has quite a bit in the far red, more than HPS does, which counts as more. However, the spectrum is for a PHILLIPS lamp with a color temperature of 4000K, but GE also makes a better CMH than PHILLIPS, it costs close to $100, but lasts longer and has a lower color temperature of 3000K. I would like to compare the GE lamp to the Phillips lamp for spectrum, but GE doesn't publish it; since the GE CMH is 3000K, it will even be more rich in the far reds and may even start to be as good as an HPS for plant-lumens/watt. Basically, the bottom line is that it is not possible to beat HPS, HPS has them all beat, but for the early growing periods, like the first half of the grow, I would use a GE CMH because of the beneficial effect on PLANT MORPHOLOGY, setting up the basic structure and skeleton of the plant, is better with CMH. Or you could use a pulse start metal halide for the first half of the grow, which would be just as good, since the blue component is important in the formative stages of plant growth. Towards the end we are just "fattening up" the plant, with piles of THC, just like a farmer fattens up the cattle, after they have had their mother's milk during the first part of their lives. The CMH is like mother's milk, and the HPS is like the grain feedlot. Peace, Sativa.
750 .000 .032
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ceestyle
Well-Known Member
The way this actually should work is this - all the spectra given for bulbs, e.g. here, are given in relative units. And no, it's not adjusted for lumens - it's the raw spectrum, but normalized to 100% intensity at the maximum. You therefore must multiple by the normalized photopic spectrum to find the spectrum that they used to calculate lumens, integrate the area under the curve, and find a scaling factor. Using that, you can scale the raw spectrum, multiply times the normalized PAR spectrum, and integrate to find PAR watts. That is, of course, after you have digitized all of the spectra. Go for it.
The web link you provided is a crude approximation even as presented, and still requires digitizing curves at integer values of the spectrum. Because there exist large spikes and the curves are not smooth, it is a weak technique and, again, a PIA.
Okay, well now we're speaking the same language. I just didn't really know what point exactly you were getting at ...
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The point I was getting at was:
1. You made me do some research and I came up with a useful article not yet quoted, but demonstrates for sure what a PAR curve looks like, from an academic source, and not a commercial lamp salesman source, and real numbers that show how to convert a spectrum into plant lumens.
2. That you made me do the research for myself, that would suggest that for the formative stages of plant growth (vegetative and early flowering), that CMH would be suitable, probably more than an HPS, and likely is superior to an MH conversion, and probably even superior to a pulse start metal halide. The difference between CMH and a pulse start metal halide is not much, except the spectrum shows the CMH output extending way out into the far red, so I suspect it has better plant lumens than a PSMH.
3. This article basically settles the debate, because the article shows actual numbers for plant lumens per watt, and HPS has 'em all beat, so for fattening up the plant, like livestock in a feedlot, use HPS.
4. There is however, an opinion that blue and violet light simulates high altitudes, and may increase potency. If you are of that opinion, consider supplementing your HPS with CMH towards the end of flowering, like the last 6 weeks. Example: for a 3x5 foot closet or grow area, two 400w HPS and a central 400w CMH might be appropriate. Someone from earlier on said that more light is always better. Even though the GE lamp costs almost twice as much, it lasts longer, has a lower color temperature so is richer in reds, and has a higher output, so that is the one I would use. If you subscribe to this belief, for example you could veg with one 400w CMH for four weeks. Flower for two weeks with 2 400w HPS. Complete four more weeks of flowering with 2 x hps and 1 x cmh.
4. I must have had too much coffee when I said you were stoned, my apologies.
Peace and out. Sativa.
1. You made me do some research and I came up with a useful article not yet quoted, but demonstrates for sure what a PAR curve looks like, from an academic source, and not a commercial lamp salesman source, and real numbers that show how to convert a spectrum into plant lumens.
2. That you made me do the research for myself, that would suggest that for the formative stages of plant growth (vegetative and early flowering), that CMH would be suitable, probably more than an HPS, and likely is superior to an MH conversion, and probably even superior to a pulse start metal halide. The difference between CMH and a pulse start metal halide is not much, except the spectrum shows the CMH output extending way out into the far red, so I suspect it has better plant lumens than a PSMH.
3. This article basically settles the debate, because the article shows actual numbers for plant lumens per watt, and HPS has 'em all beat, so for fattening up the plant, like livestock in a feedlot, use HPS.
4. There is however, an opinion that blue and violet light simulates high altitudes, and may increase potency. If you are of that opinion, consider supplementing your HPS with CMH towards the end of flowering, like the last 6 weeks. Example: for a 3x5 foot closet or grow area, two 400w HPS and a central 400w CMH might be appropriate. Someone from earlier on said that more light is always better. Even though the GE lamp costs almost twice as much, it lasts longer, has a lower color temperature so is richer in reds, and has a higher output, so that is the one I would use. If you subscribe to this belief, for example you could veg with one 400w CMH for four weeks. Flower for two weeks with 2 400w HPS. Complete four more weeks of flowering with 2 x hps and 1 x cmh.
4. I must have had too much coffee when I said you were stoned, my apologies.
Peace and out. Sativa.
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BigBudBalls
Well-Known Member
Hey Cee,
I keep hearing that plants don't use/can't see green. But every one of the PAR curves I look at (they all seem to look the same) do not drop off for green. In fact, its higher in the green then the blue.
Just wondering on your thoughts about it.
I keep hearing that plants don't use/can't see green. But every one of the PAR curves I look at (they all seem to look the same) do not drop off for green. In fact, its higher in the green then the blue.
Just wondering on your thoughts about it.
ceestyle
Well-Known Member
You know, that's a good question. I have found a number of PAR curves that look like this and this , but I have also seen a few that look like this, which would be consistent with green being much less useful for plants. I have yet to unearth a concrete source besides the book cited in the last article (which of course I do not own) which cites one of these with proper units. I assume that the two first references and all like it are in energy, while the second type is in photon flux, but converting using the wavelength does not result in the PAR spectrum heavy in green that we normally see.
If someone has a citation, I would be eager to see it. I suppose I could dig out a bio book or two, but I'm loathe to do that.
ceestyle
Well-Known Member
Well put. Thanks for the discussion. The article you posted has a couple useful refs that I requested above. I'll take a look at those.
Cheers.
cc
ThatOneDude
Well-Known Member
ceestyle, eariler you asked why someone would switch back to a cmh blub at the end of flower. I've read about a few people doing this and it's a split discusion at this point. The thinking behind it is that becasue the CMH bulb puts out UVB light that it will force the plant into protecting itself againt it by producing more thrics. Again, that's something that is split at this point and honestly I haven't been following it much anymore.
At this point there are plenty of grows that have gone through using CMH and from what I've seen it's coming out even as far as yeild, people say they end up with a more leafy bud and more thrics. I'm talking about grows where people have run the same strain over and over again, then switched to CMH, some go back to HPS some say the never will. To each their own.
Nobody I've seen yet has said they were going back to an MH bulb for veg. I'm using 1000 watts for flower and the 400 watt cmh for veg in a cab.
At this point there are plenty of grows that have gone through using CMH and from what I've seen it's coming out even as far as yeild, people say they end up with a more leafy bud and more thrics. I'm talking about grows where people have run the same strain over and over again, then switched to CMH, some go back to HPS some say the never will. To each their own.
Nobody I've seen yet has said they were going back to an MH bulb for veg. I'm using 1000 watts for flower and the 400 watt cmh for veg in a cab.