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whiterasta
As a vegetative light only they are effective @~4-5ft on 12-18" plants. @ ~2' they are good for about 2-2.5ft of solid penetration during flower
I
inphu510n
So the real question is, how do you smoke your puppies afterward?
220*f at about half hour per pound. I prefer hickory, although maple wood ain't bad!
For all those waiting for a 1000w Philips CMH, you can stop waiting and give it up. Having emailed one of Philips Lighting PR people who's contact info I found in a press release, my emails got bumped up to the head of Philips lighting division on the question of whether a 1000w was still in the works, as was vaguely promised at the release of the 400's. He said Philips has no plans to produce a 1000w version of the CMH.
BakedBeans
Member
Looks like us hobby/medicinal growers will have an edge.
600-1000w is good for commercial, 400w is plenty for patients.
bb
600-1000w is good for commercial, 400w is plenty for patients.
bb
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whiterasta
That is actually OK as I have found the holy grail of lights. A 1k HPS + .4k CMH! whiter light, bushy dark green plants with coarse thick stems and plants that are the best I have grown in 20 yrs indoor.I lead in 2 hrs and out 2hrs with cmh then burn both for the middle 8 on 12/12. On 18/6 I lead in 3hrs and out 3hrs and burn both for 12. Pics tonite at "daybreak" of a comparison of before the CMH and after.But to anyone with the capability I would highly recommend using a .4k along with your 1k HPS the difference is truly amazing.
One thing, when the clones went from CFL to the big lights they, first off began growing very fast but not stretching then within 4days the oldest shade leaves( left from the original cuts of the clones) all curled up and burned due to the intensity of the light.Temps at my canopy peak @ >81F in the furthest corner and the soil mix is a long proven blend. The only variable was the added spectra.I culled about 3-5 leaves from each plant before the new growth wiped any traces of the burn away. ATM they are fluorescent green at the meristem and a dark burly green in the body, stems are thick and fibrous and the root systems are more advanced then I have seen in an indoor plant. In fact the plants look much more like potted outdoor plants than indoor. But as I said I will let the pics speak after lights tonight.
For myself I will be using this combo of 1k+.4k most likely until they can just be in the sun.
Once again if you have the capability check out the combination. It simply outperforms every other light combo I have ever seen and I have tried everything but a 10k aquarium bulb (thought them overkill blue) including the dual arc tube .6/.4K combos.Nothing even comes close to what I am seeing now
WR
One thing, when the clones went from CFL to the big lights they, first off began growing very fast but not stretching then within 4days the oldest shade leaves( left from the original cuts of the clones) all curled up and burned due to the intensity of the light.Temps at my canopy peak @ >81F in the furthest corner and the soil mix is a long proven blend. The only variable was the added spectra.I culled about 3-5 leaves from each plant before the new growth wiped any traces of the burn away. ATM they are fluorescent green at the meristem and a dark burly green in the body, stems are thick and fibrous and the root systems are more advanced then I have seen in an indoor plant. In fact the plants look much more like potted outdoor plants than indoor. But as I said I will let the pics speak after lights tonight.
For myself I will be using this combo of 1k+.4k most likely until they can just be in the sun.
Once again if you have the capability check out the combination. It simply outperforms every other light combo I have ever seen and I have tried everything but a 10k aquarium bulb (thought them overkill blue) including the dual arc tube .6/.4K combos.Nothing even comes close to what I am seeing now
WR
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whiterasta
I made dual foci parabolics to maximize not only the spread but the mixing of spectra that ride on a 5' travel lightrail
as far as penetration the 1k drives that while the .4k drives the full use of all photosynthetic peaks.Besides seeing how my plants respond to the .4k a 1k IMO would be too much UV(?) for a normal ceiling height.
WR
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whiterasta
so here is an example of how much the .4k CMH alters the spectrum when mixed with an HPS 1k
first is the .4k CMH
next is the combination
Finally HPS alone
Plant under CMH alone
Under combo HPS/CMH
WR
first is the .4k CMH
next is the combination
Finally HPS alone
Plant under CMH alone
Under combo HPS/CMH
WR
LovableHuggable
Member
Wonder what one of these will do in a micro grow box like a 2'x2'x2' one? How hot do they get compared to HPS or regular MH?
LovableHuggable
Member
I thought after reading about these bulbs the whole point of CMH was to use it for both veg and flower as it offered both MH and HPS in one bulb. Maybe I need to read the whole thread and not just skim it.
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whiterasta
I want to add I have done this for over 20 yrs now beginning by reassembling industrial lighting. I discovered the hard way that MV and LPS kill plants, that flourescents make fluffy buds, and that old MH bulbs are shit. I have studied light metabolism and chlorophyll/carotene.
The only reason plants grow under HPS is it hits the peak of absorption of the main pigment. That CMH actually provides a flat complete spectrum including UV should be where one starts when looking into the bulb. Since it is not yet made for horticulture by the manufacturer it falls to the user to understand the proper way of using it.
WR
The only reason plants grow under HPS is it hits the peak of absorption of the main pigment. That CMH actually provides a flat complete spectrum including UV should be where one starts when looking into the bulb. Since it is not yet made for horticulture by the manufacturer it falls to the user to understand the proper way of using it.
WR
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whiterasta
as they say the proof is in the pudding so here is a comparison of my floor from 5 days ago to today @ very close to 6" of tight growth and showing flowers I have never seen my floor look so fine in less than a week from turn back
And 5 days later 6" new growth and flowers on my early bird strain
And 5 days later 6" new growth and flowers on my early bird strain
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whiterasta
IME this is the new hot thing in light even before LED. Some folks have made a mistake using them however. They try and use them like a MH for veg then switch to HPS for flower. BIG NO NO! that will stress the plant to hermie the CMH is a stand alone lamp or a mixed spectrum with HPS. going from CMH to HPS cuts the production of three main pigments from the plant and stresses it badly( light malnourishment).
Look at the diagram of HPS's SPD overlayed on the CMH SPD. You will see the CMH hits all major pigment absorption peaks while HPS only hits Phycoerythrin and less phycocyanin. When one goes from CMH to HPS the plant is cut back drastically on photosynthetic output as B-carotene, chlorophyll A and B are not stimulated at all by HPS.
The first diagram shows the difference in HPS vs CMH, the second shows the expectations of a plant for photosythesis.
As one can see HPS is only providing for ~half the necessary spectrum for complete phtosynthesis.
For folks who have had problems in using CMH to veg and HPS to flower look at the overlay of the SPD of HPS over CMH then check out the absorption peaks of the photosynthetic pigment. Note that more than half the pigments are not even touched by HPS while CMH covers the whole range. When one goes from pure CMH to pure HPS it effectively cuts the leaf output in half and stresses the plant
SPD of HPS overlayed on SPD of CMH
Absorption peaks of major photosynthetic pigments
As one can see HPS really only hits phycoerythrin and phycocyanin.
Chlorophyll A&B and B-carotene are not. Now take a plant that is metabolizing on all pigments and remove three of them. This is what the CMH veg to HPS flower does.
AS I said CMH is a stand alone for small spaces and an HPS blend for large grows. It may throw white light like a MH but it is as different as night and day to the plants.
Hope this clears up some misconceptions about the CMH bulb and how it is used.
WR
Look at the diagram of HPS's SPD overlayed on the CMH SPD. You will see the CMH hits all major pigment absorption peaks while HPS only hits Phycoerythrin and less phycocyanin. When one goes from CMH to HPS the plant is cut back drastically on photosynthetic output as B-carotene, chlorophyll A and B are not stimulated at all by HPS.
The first diagram shows the difference in HPS vs CMH, the second shows the expectations of a plant for photosythesis.
As one can see HPS is only providing for ~half the necessary spectrum for complete phtosynthesis.
For folks who have had problems in using CMH to veg and HPS to flower look at the overlay of the SPD of HPS over CMH then check out the absorption peaks of the photosynthetic pigment. Note that more than half the pigments are not even touched by HPS while CMH covers the whole range. When one goes from pure CMH to pure HPS it effectively cuts the leaf output in half and stresses the plant
SPD of HPS overlayed on SPD of CMH
Absorption peaks of major photosynthetic pigments
As one can see HPS really only hits phycoerythrin and phycocyanin.
Chlorophyll A&B and B-carotene are not. Now take a plant that is metabolizing on all pigments and remove three of them. This is what the CMH veg to HPS flower does.
AS I said CMH is a stand alone for small spaces and an HPS blend for large grows. It may throw white light like a MH but it is as different as night and day to the plants.
Hope this clears up some misconceptions about the CMH bulb and how it is used.
WR
FWIW, I've had some herms under CMH alone, never using a CMH/HPS switch.
knna
Member
Just a note, whiterasta, superior plants dont have Phycoerythrin nor Phycocyanin. Anyway, the point about the broader spectrum inducing better quality is valid. Not so much a proven scientific truth than an empiric observation.
Superior plants use clorophills mainly, and accesorily, carotenoids. There are many carotenoids and some absorb well in the range you refered to, but beta carotene, the by far most present carotenoid have its range on the cyan, as the graph shows.
Use of light by plants is far more complicated that you can extrapolate from lab absortion of photosyntetic compounds. In vivo plants, they perform on a very different way. Chorophils, and specially chlor b, absorb very well on the orange. If not, HPSs wont work as they work for growing, as they emits more than 80% of the energy on the yellow-orange. But plant grown on this narrower spectrums need to change deeply the pigments used, when compared with same plants under broader spectrums (sun, Metal Halides). Usually HPS grown plants have at least double chlor b than sungrown plants. Photosynthesis is little affected, but some other things notice the difference.
So at the end, we can conclude CMHs works because people is using them with excelent results. When we have that, there is no any need for any other arguments. In fact, if you analyze CMH spectrum for its photosynthetic efficacy, its slightly lower than HPSs efficacy on the paper. But plants grow happier, with less radiant heat and under a spectrum more similar to which they evolved to use better.
There is some stupit need of some people to find the "best" growing lamp (Im not refering to you, whiterasta), and once they select one, they think it must be better on all ways of use. There is no such thing. Different lights have different advantages and disadvantages, some adapt better to some environments, some to others. CMH is working fine, no doubt. For some people, they are working way better than any other type of lighting. Some growers has found that they get the best when they mix HPS and CMH. Others, when coupling a 4200K CMH with deep red LEDs. Some tried CMH and back to HPSs.
The great thing about 400W CMHs is they use HP ballast, so any grower using a HPS can try a CMH for very little money and find for himself if they works better on his grow.
This thread is great for CMH's growers share their experiences with them, and how they got the best of them. You are doing a great work on this
Superior plants use clorophills mainly, and accesorily, carotenoids. There are many carotenoids and some absorb well in the range you refered to, but beta carotene, the by far most present carotenoid have its range on the cyan, as the graph shows.
Use of light by plants is far more complicated that you can extrapolate from lab absortion of photosyntetic compounds. In vivo plants, they perform on a very different way. Chorophils, and specially chlor b, absorb very well on the orange. If not, HPSs wont work as they work for growing, as they emits more than 80% of the energy on the yellow-orange. But plant grown on this narrower spectrums need to change deeply the pigments used, when compared with same plants under broader spectrums (sun, Metal Halides). Usually HPS grown plants have at least double chlor b than sungrown plants. Photosynthesis is little affected, but some other things notice the difference.
So at the end, we can conclude CMHs works because people is using them with excelent results. When we have that, there is no any need for any other arguments. In fact, if you analyze CMH spectrum for its photosynthetic efficacy, its slightly lower than HPSs efficacy on the paper. But plants grow happier, with less radiant heat and under a spectrum more similar to which they evolved to use better.
There is some stupit need of some people to find the "best" growing lamp (Im not refering to you, whiterasta), and once they select one, they think it must be better on all ways of use. There is no such thing. Different lights have different advantages and disadvantages, some adapt better to some environments, some to others. CMH is working fine, no doubt. For some people, they are working way better than any other type of lighting. Some growers has found that they get the best when they mix HPS and CMH. Others, when coupling a 4200K CMH with deep red LEDs. Some tried CMH and back to HPSs.
The great thing about 400W CMHs is they use HP ballast, so any grower using a HPS can try a CMH for very little money and find for himself if they works better on his grow.
This thread is great for CMH's growers share their experiences with them, and how they got the best of them. You are doing a great work on this
