Ceramic Metal Halide (CMH)

[gramsci.antonio]

Some updates: 2 plants @ 3rd day of flowering, from 10 days under a 400 W CMH:







Some leaves got ****ing GIANT

 

[gramsci.antonio]

I say it from direct analysis of the bulbs. Its not a theoretical statement.

can you link some data

How this energy efficiency translates into a uE/consumed watt ratio (uE= micromol of photons) is influenced by the SPD (spectrum). The shorter the wavelenght emited, the lower the uE/w ratio (for same PAR watts). I have calculated how many uE are in either a Klm or a PAR watt of several bulbs.

Anyway, CMH 830 spectrums are more similar to HPSs
spectrums than traditional (quartz) MHs. Specially compared to blue enhanced HPS.

So the problem is: we have to measure the efficency.

 

[gramsci.antonio]

Several botanist studies shows that total dry matter accumulation is very closely related to photons intercepted by plants. And these studies have been performed over several plants species. Desviations are below 10%. Throw 30% more photons to your room and you may expect a 30% increase in yield (except if your garden have already a lot of light).

The problem is that different plants behave in a different to different type of light.

WAY different.

The closest plant to cannabis in the genetic map is Humulus lupulus.
Many studies are based on commercially grown plants, wich are way different than cannabis, and very very few are based on Humulus lupulus.

But again if someone make a study on Humulus lupulus it can be useless. Because we are more similar to monkeys than cannabis to Humulus lupulus.

I let you think the BIG difference between an human being and a monkey, and then imagine the ones between cannabis and Humulus lupulus.

And also hemps is different. Because it doesn't produce any THC.

For example: A light may behave VERY good with hemp, but if it lacks too much in UVB then the production in resin will be lower. Wich makes the light VERY good to grow, not good for smokers.

But photosynthesis uses any photon in the PAR range. With differences in efficacy (number of photons required to fix a C) between wavelenghts. Plants need less red photons than blue ones. Green photons are required in the larger number.

That's not true. Plants prefer blue light, and green is almost useless to growth.

Here some datas:

http://www.life.uiuc.edu/govindjee/paper/fig5.gif

Taking into account that a blue photon carry more energy (from 50 to 70% more than a red one), when using artificial lighting, the more red, the better in term of photosynthetic efficacy.

Why?

But most plant species require a amount of blue photons, and in less degree, of other wavelenghts, to grow healthy. Although ive been unable to find any scientific study about cannabis light requeriments, i believe that cannnabis is little demanding about this, as some people uses LPS to grow cannabis sucesfully, and LPS emits monocromatic light (589nm mostly).

i would like to see the results.

But of course that blue photons are far more critical for the health of plants. But it dont mean they has more photosynthetic efficacy.

See data posted above.

 

[gramsci.antonio]

I just found this great article that simplifies the situation for us. Its a very informative, interesting and brief article about the subject of usable light for plants. I highly recommend it.
http://www.agriworld.nl/public/file/pdf/20060504-fltcs7.2.pdf

So after reading that, I am left wondering what this translates to usable par light for the cmh vs say, a 1000 solarmax hps? is there some formula to posibly use.

Thanks,
payn

and if possible could u dumb it up just a tad... im having trouble deciding what is relavant, to growing better bud....

I don't want to be mean, but this is commercial bullshit.

For
good plant development, crop
structure and the colour of the
leaves it is important that the
plant receives a balanced light
spectrum.

You have to read with intelligence, from the latin meaning: the ability to understand.

It really says that a balanced spectrum is better, not that you can give any color you want and hope that the plant will grow.

 

[JohnnyToke]

Temps? RH? Strain?

temps 74-78f lights on and 62-65f lights off.

reservoir temps for full time recycling through grow buckets are 68f at all times controlled w/ chiller system.

RH - 35 - 45%

strain - B52 by Nirvana

it was not an environmental issue. it was definately a genetics issue. I got a bad seed....lol

 

[Siddartha]

Keep it up, I'm learning and taking notes!

 

[gramsci.antonio]

Bulb's analysis Although i believe i uploaded the datasheet here at IC, in that thread is not only the datasheet, but its explained fully and there are several bulbs analyzed. Phillips CMD 400w is in post 31 and 32# (page 4).

intersting. I'm reading it.

What's PPF?

As most concepts asked here are alredy answered in that thread, i wont return on them. But i would like to clarify some things that have been said in the last post that are clearly false.

1-Terrestrial plants have the same photosynthetic system. Photosynthetic effect is very similar from one to others. Differences have been accurately measured at botanist studies. Most known are those from Inada and McCree. Mc Cree curve is shown in the pdf linked by payn4school, wich BTW, is very good (not bulshit at all).

Can you post something related from Inada or McCree regarding the "accurately measured [difference] at botanist studies"?

I'm really intersted.

But those studies are performed under sunlight adapted plants (Mc Cree used too some plants grown under HPSs). Plants adapt their photosyntetic antennas changing the percentage of each light absorbingh pigment (chlorofills a and b, carotenoids, etc), in order to use the light they are receiving the best.

any evidence?

2-Although there is no any scientifical study about light requeriments and effect over cannabis, we have avalaible very accurately the absorbance/reflectance/transmitance of cannabis, at different stages of grow, wich allow us to compare bulbs for MJ growing.

Yeah, in fact we found that blue light decrease the yield, while increasing potency and density of buds

3-Plants use green photons too. With less efficacy, but not so much as many people tend to think. Photosynthetic effect of green photons is similar to blue photons one. The only difference is higher absorbance of blues respect to greens (thats why we see plants green, but it dont mean at all that plants reflect back all green photons). Green photons reflectance is about 10% more than blue ones.

that's absolutly not true. Especially the bold part.

According to this:

http://www.life.uiuc.edu/govindjee/paper/fig5.gif

If 100 W of light at 440 nm is transformed in 100 W of energy for the plant, then at 555 nm 100 W of light is trasformed in 23-24 W of energy for the plants. The remaining 80 W are reflect or converted to Heat.

Green light isnt wasted, as many people repeat. That statement is completely false, but its a very persistent myth.

I think that plants need the whole spectrum, i wouldn't be surprised if some enzyme would need green light. But around 80% of 555 nm radiation (green) is wasted.

 

[gramsci.antonio]

Anyhow, thermodinamically speaking, a lamp is like an engine.

It absorb Energy (E) and trasfrom it in Work (W) + Heat (Q)

E=W+Q

If we define efficency (dW) as:

f(E, W) --> [0, 1)= W/E

A function of Energy and Work to the set of real numbers [0, 1) then

dW=(E-Q)/E=1-Q/E


So, because we know the energy that the bulb absorb (150, 250, 400...) we just need to know the quantity Q.
Q is a measure of the heat flow=

Q=m*dT

Where m is the mass of the lamp and dT is the difference in temps when the lights is on and off.

So the best way to measure the efficency of different lamps in a given system (different system will give different value, due to different enviromental condition) is to measure the the weigth of the lamp, and then with an infrared termometer measure the dT of the lamp.

 

[simba]

Im going to make this short and sweet,

when you stand back both sides of the argument support using CMH for growing.. Kinda funny Ay??

in short G and K are both right in there own rights ..

some say ya green some say no green light.. Ill say this.. it needs a lil.. but not much compared to others.. (the colors the plant uses the least/reflect is what we see IE GREEN)

Plants need FULL SPD..

lets go back to solar panels new vs old versions..
old version only accepts and transforms a Small window Of nM Ranges and outputs very lil power compared to new style..
New Version accepts and transforms a Large window Of nM Ranges therefor outputting more power from the sun..
they have shown by increasing the NM range they can make the plate smaller to achieve the same result if not better as the Narrow versions.
now lets reverse that..


canna under hps will grow but require more power at that narrow Nm range
than canna under cmh..

if you give a plant full spd, it can now effeciantly grow whereas under HPS they have to clam around a small range of NM energy..

ya ill give it id like if the overall outputted energy was a bit more but we already got the sun handed to us.. we can wait for RF CMH for Crazy Full SPD Power..

when i talk to commercial opps i recommend switching out there 600s or 1kws and go to 400 cmh's

example: few customers have 6 - 600watters over 6'x9' tables and when they go to CMH they have no regrets.. (ya some its a challenge to forget what they know) and none of my Recommendations have come back and said WTF. it dont work..
infact most comeback and say thanks for pushing so dam hard.. Not as a self pat...
(again i love multi cmh lamps in the grow room vs 600 or 1kw)
so much light and energy is just plain old lost from the extra height needed with HPS>>

ya the debate im fine if linked to this thread but ya it needs its own page..
but we dont know enough data regarding canna and light sources so we have to go with what shows that it works (cmh) from actual results from using it..
lets go back to hps min of 25%+ of its energy is outright wasted, out of the rest 10% is wasted cause its peaked above what the plant can even absorbe.
and then the "lume Loss" 60-70% hold.. so at 5k hours you now have less energy than CMH (overall, useable) at same time in its life.. and then threw the rest of there life CMH is outperforming..

 

[MostHigh]

Philips' CMH and Venture's 950 PSMH causes people's brains to hurt while they stubbornly cling to the notion that HPS is the best source of light for indoor growing/bloom. Denial mode kicks in for them...they'd rather not realize they've been using over-priced substandard lighting.

 

[gramsci.antonio]

example: few customers have 6 - 600watters over 6'x9' tables and when they go to CMH they have no regrets.. (ya some its a challenge to forget what they know) and none of my Recommendations have come back and said WTF. it dont work..
infact most comeback and say thanks for pushing so dam hard.. Not as a self pat....

i understand you are a salesman and you have to push for your product. But i seriously doubt that a 400 W CMH can compete with a 600 W HPS/MH.

By myself i doubt that CMH are suitable for growing cannabis. There has been neither a comparison grow nor a complete grow yet.

That's why i'm going to look by myself.

 

[MostHigh]

If the Philips CMH isn't suitable for growing MJ...what pray tell is Hortilux's mega-spendy 1000 watt super-blue doing on the market?


vs

 

[gramsci.antonio]

If the Philips CMH isn't suitable for growing MJ...what pray tell is Hortilux's mega-spendy 1000 watt super-blue doing on the market?

I'll express myself better:

I think we can achieve better results using different bulbs.

For example: a LOT of energy is wasted around 550 nm, wich is almost useless for the plant...

 

[MostHigh]

I'll express myself better:

I think we can achieve better results using different bulbs.

Agreed. That'd be why I have more lamps than I know what to do with.

 

[gramsci.antonio]

Agreed. That'd be why I have more lamps than I know what to do with.

what are you waiting for? start immediatly a side by side comparison

If you can't grow weed just go for Humulus Luppulus, wich is similar enough...

 

[MostHigh]

gram...one vehicle is rated as 20 MPG, another is rated at 50 MPG.
Are ya really going to fill up the 20 MPG vehicle to realize it's fuel economy sucks ass compared to the 50 MPG vehicle?
Like many, I'm tight on space...doing a side-by-side for sake of supplying pictures to growdum...sure, soon as someone delivers me material to construct a seperate space and sponsors my utility bill...I'll get right on it.
See...I'm well into the notion regarding HPS as a substandard waste of time and energy.

 

[Siddartha]

Both kill flouros, though, right? :-D

J/K, not trying to start no shit, just trying to lighten things up a bit.

Man, there's tons in this thread to ic/wikipedia/google....

 

[Murphy]

i understand you are a salesman and you have to push for your product. But i seriously doubt that a 400 W CMH can compete with a 600 W HPS/MH.

.......I doubt he is posting all of this info and answering all of these questions to sell a couple $53 light bulbs......

 

[gramsci.antonio]

.......I doubt he is posting all of this info and answering all of these questions to sell a couple $53 light bulbs......

my grandma always said to think bad about people

 

[MostHigh]

Ya...simba isn't caring about where ya get it. His concern is simply turning people on to that its out there.
He's been at it for a couple years now...the skepticism he's encountered along the way is disturbing considering lamp technology is still fairly new to humanity...still in it's infancy with regards to indoor argiculture.
People act like fuk'n HPS is the hands-down-all-time-champion of indoor growing...20 years from now, HPS will be a term tough to locate on the world wide web.