Ceramic Metal Halide (CMH)

[zachrockbadenof]

others here will have much more info then me, but i'm using '2' 315's in a 4ftx3.5ft tent and i think the lite is insuff... i am adding '2' cheap led's , one on each side to try and supplement the lites- last yr i tried adding an 8bulb 4ft fluor, but it cooked the plants

 

[Miraculous Meds]

@miraculous-

those buds look lovely! Almost looks like a hash plant.

I appreciate the link to the 315 LECs! LEC > CMH, correct?


And Do you think that 5 or 6 of the 315w LEC's will light a 3'x15' table very well? For bloom as well as veg? Your 630 looks like it had decent canopy penetration and decent intensity but its hard for me to guess how well a 315 watter would compare. Id imagine that it would have to be closer to the canopy, and closer together as well.

I'm still debating how much better my tables would be and how much higher production would be if I lit the 3x15 with 5 600 watt HIDs.


My main goal is for the room to be able to veg or bloom with great vigor and health. Its a production room, so I wouldnt care about spending more money on electricity/cooling if it meant the plants were vegging/blooming more vigorously and healthily.


Also- am I correct to assume that the 4200k bulbs would be better for veg and the 3100k bulbs would be better for bloom?

Id go with 6 for production, and 5 would be more than plenty for hearty veg. I run a cheap 315 over a starting veg spot and i get extreme vigor within 2.5'x2.5', if there were side lighting from more a 3x3 coverage works great. Ive seen people raise the 315s 4' over canopy to keep veg moms going in 4.5'x4.5' footprint, but ime, for extreme vigor, 1 315 for 2.5', or multiples on 3'.

If your comparing the 315s to 600hps, dont. Run 630cmh if you want more yield, you will be happy.

4200s more for veg, 3100s for flower. A lot of people use them both ways. I have little experience with 4100s except in veg. Also people mix them.

 

[Zarezhu]

You get extreme vigor over a 2.5x2.5 with a 315 LEC? Or CMH? Am I correct to assume that LECs are superior to CMHs?

I have looked into the 630w CMH's, the DE's, they're just soooo much more pricey than a traditional 600w HPS. $450 a piece for 10 630w DE cmhs lights versus under $200 a piece for 10 standard 600w HPS.

Unfortunately, I think my two ton mini split would struggle keeping up with 6000w of light in the room. It can handle 4000w with ease, can likely handle 5kw as well. I may be able to aircool the lights if I decide I want to run 6000w.

Maybe I could get by with running 4 of the DE 630s per 3x15 table? On second thought, I'm not sure that I have enough headroom to run 630w DE's in this room. I feel I could get HPS much closer to the canopy without burning than a DE, but thats from my limited experience with 1000w gavitas.


I'm curious why you say you cant compare the 315 to a 600w HPS?

12 of the 315s is just under 4kw. Im curious if the 4kw will yield comparably with an equal wattage of HPS, accounting for the extra penetration through the canopy and such. Simply comparing flowering results/yield, watt for watt


edit: also, the 630w CMH is good for a 4x4 bloom area, correct? and a 600w hps is 3x3? Im limited to 3' wide tables and dont exactly want to waste $$ by lighting my walkway.

 

[Natural high]

You get extreme vigor over a 2.5x2.5 with a 315 LEC? Or CMH? Am I correct to assume that LECs are superior to CMHs?

CMH and LEC are just different terms for the same light.

I'm curious why you say you cant compare the 315 to a 600w HPS?

I think what he means is that a 315w CMH can not complete with a 600w HPS. 2 x 315w obviously will, or a 630w.

 

[Jhhnn]

CMH and LEC are just different terms for the same light.

I think what he means is that a 315w CMH can not complete with a 600w HPS. 2 x 315w obviously will, or a 630w.

630w of CDM will radically out perform 600w of HPS. It's closer to the performance of 1000w of HPS.

 

[Jhhnn]

You get extreme vigor over a 2.5x2.5 with a 315 LEC? Or CMH? Am I correct to assume that LECs are superior to CMHs?

I have looked into the 630w CMH's, the DE's, they're just soooo much more pricey than a traditional 600w HPS. $450 a piece for 10 630w DE cmhs lights versus under $200 a piece for 10 standard 600w HPS.

Unfortunately, I think my two ton mini split would struggle keeping up with 6000w of light in the room. It can handle 4000w with ease, can likely handle 5kw as well. I may be able to aircool the lights if I decide I want to run 6000w.

Maybe I could get by with running 4 of the DE 630s per 3x15 table? On second thought, I'm not sure that I have enough headroom to run 630w DE's in this room. I feel I could get HPS much closer to the canopy without burning than a DE, but thats from my limited experience with 1000w gavitas.


I'm curious why you say you cant compare the 315 to a 600w HPS?

12 of the 315s is just under 4kw. Im curious if the 4kw will yield comparably with an equal wattage of HPS, accounting for the extra penetration through the canopy and such. Simply comparing flowering results/yield, watt for watt


edit: also, the 630w CMH is good for a 4x4 bloom area, correct? and a 600w hps is 3x3? Im limited to 3' wide tables and dont exactly want to waste $$ by lighting my walkway.

LEC is a marketing term for 315w Philips CDM tech.

Watt for watt, 315 cdm's will radically out perform conventional hps. You can also run the lights much closer to the tops because there's radically less infrared.

 

[Natural high]

630w of CDM will radically out perform 600w of HPS. It's closer to the performance of 1000w of HPS.

It seems this argument is never ending. I have used both a 600w single-ended hps and 2 x315w CMH in separate runs in the same 1.16m x .92m grow box. The 600w hps beats the 2 x 315 in yield and bud density but the CMH flowers have more frost and terps. There is no way 630w of CMH can complete with 1000w of hps.

Cheers

 

[Jhhnn]

It seems this argument is never ending. I have used both a 600w single-ended hps and 2 x315w CMH in separate runs in the same 1.16m x .92m grow box. The 600w hps beats the 2 x 315 in yield and bud density but the CMH flowers have more frost and terps. There is no way 630w of CMH can complete with 1000w of hps.

Cheers

I would suggest that some other variable is responsible for your observed results. It's contrary to my experience & to that of other thread contributors.

 

[Phaeton]

I would suggest that some other variable is responsible for your observed results. It's contrary to my experience & to that of other thread contributors.

I ran a test room using between 800 and 1600 watts in a four by four area. Two years of testing lights against each other.
Clones were used for consistency and all runs had a matched control plant.

HPS has not been used at all since the testing. Folks get emotional about this so not often I mention HPS testing.

I have made my living at gardening exclusively since 2010.
Science is science whether you believe or do not believe so I do not intend to argue the results of years of testing.
There is a perfectly logical reason for HPS having a fanatic following, has to do with word of mouth learning and lack of public information back in the day when mercury vapor or sodium were the only choices.
Sodium (Orange and green) grew plants and the mercury HID (blue and violet) killed plants, easy choice and passed on to each and every new grower for the twenty years it took to develop the technology to replace the primitive sodium bulbs. The change from almost a mono wavelength emission without blue and very little deep red to full spectrum is so great it is difficult to even compare them.
Truth is slowly replacing word of mouth, but slowly is the catchword. As long as growing is illegal it will be taught by anyone with a garden, regardless of knowledge level.

 

[Scrappy-doo]

It seems this argument is never ending. I have used both a 600w single-ended hps and 2 x315w CMH in separate runs in the same 1.16m x .92m grow box. The 600w hps beats the 2 x 315 in yield and bud density but the CMH flowers have more frost and terps. There is no way 630w of CMH can complete with 1000w of hps.

Cheers

Current run with 945w of cmh in a 4x8 @51 days:

My last run with 1800w of hps in a 4x8:

Want to take a guess which is going to yield more?

 

[gh0stm0de]

What ballast are you using for the 945, Scrappy? Or is it 3x 315?

 

[Scrappy-doo]

What ballast are you using for the 945, Scrappy? Or is it 3x 315?

3x 315

 

[SnakePlissken]

Nice canopy.

 

[Jhhnn]

I ran a test room using between 800 and 1600 watts in a four by four area. Two years of testing lights against each other.
Clones were used for consistency and all runs had a matched control plant.

HPS has not been used at all since the testing. Folks get emotional about this so not often I mention HPS testing.

I have made my living at gardening exclusively since 2010.
Science is science whether you believe or do not believe so I do not intend to argue the results of years of testing.
There is a perfectly logical reason for HPS having a fanatic following, has to do with word of mouth learning and lack of public information back in the day when mercury vapor or sodium were the only choices.
Sodium (Orange and green) grew plants and the mercury HID (blue and violet) killed plants, easy choice and passed on to each and every new grower for the twenty years it took to develop the technology to replace the primitive sodium bulbs. The change from almost a mono wavelength emission without blue and very little deep red to full spectrum is so great it is difficult to even compare them.
Truth is slowly replacing word of mouth, but slowly is the catchword. As long as growing is illegal it will be taught by anyone with a garden, regardless of knowledge level.

What a lot of people don't realize about HPS is that there's a huge spike of wasted energy out in the infrared, energy that plants can't use. CDM's put that energy into the visible range where plants can use it. Rives posted this link long ago-

https://www.cycloptics.com/sites/default/files/USU_spectral_analysis.pdf

Watt for watt, they should beat the pants off of HPS, and they do imho. If they didn't, I'd figure there was some other aspect of it where I wasn't doing it as well.

Back in 2015 the barriers to entry into CDM's were much higher. They were for tinkerers & used parts scroungers like myself. It was nearly all 200-277v. Grow fixtures per se were just coming onto the market. There wasn't much available beyond Philips industrial stuff & they discouraged marketing from distributors to growers for political reasons. We're still their bastard child they don't want to talk about. The entry of third party manufacturers changed all that although the up front price is still on the high side. That difference turns to a grower's advantage over time because they're a lot more efficient & because lamps last a lot longer, at least genuine Philips lamps do.

 

[Natural high]

What a lot of people don't realize about HPS is that there's a huge spike of wasted energy out in the infrared, energy that plants can't use. CDM's put that energy into the visible range where plants can use it. Rives posted this link long ago-

https://www.cycloptics.com/sites/default/files/USU_spectral_analysis.pdf

Watt for watt, they should beat the pants off of HPS, and they do imho. If they didn't, I'd figure there was some other aspect of it where I wasn't doing it as well.

A 600w hps puts out 90,000 lumens, which is a measure of visible light in the 400-700nm range - it doesn't include the infrared peak which is outside the visible spectrum.

A 313w CMH puts out 33,000 lumens, which is equivalent to 62,857 lumens per 600 watts. CMH also has a significant peak in the infrared range.

Don't get me wrong, I like CMH and watt for watt they give a similar yield to hps. The buds have better terps and resin, but they are leafier and don't have the density and shear size that a hps can produce in my experience.

I grow sativa-leaning hybrids and find that the stretch that occurs with HPS is another advantage over CMH for my style of growing.

Here is one of my buds under 600w hps from a plant that yielded over 20 oz. When I get similar buds from CMH I'll let you know.

 

[Jhhnn]

A 600w hps puts out 90,000 lumens, which is visible light in the 400-700nm range - it doesn't include the infra-red.

A 313w CMH puts out 33,000 lumens which is equivalent to 62,857 lumens per 600w equivalent.

Don't get me wrong, I like CMH and watt for watt they give a similar yield to hps. The buds have better terps and resin, but they are leafier and don't have the density and shear size that a hps can produce in my experience.

I grow sativa-leaning hybrids and find that the stretch that occurs with HPS is another advantage over CMH for my style of growing.

Here is one of my buds under 600w hps from a plant that yielded over 20 oz. When I get similar buds from CMH I'll let you know.

View Image

Lumens are a measure weighted to the sensitivity of the human eye. Plants, otoh, respond to Photosynthetic radiation, PAR, basically the whole visible spectrum.

https://www.lumigrow.com/demystifying-lumens-lux-and-par/

Radiation outside of the visible spectrum is wasted energy when it comes to plant growth & HPS wastes a lot in that huge infrared spike. It can be no other way.

CDM's move that energy into the visible range where plants can use it.

 

[Zarezhu]

@Natural High- appreciate your insight. I had a feeling that yield/density would be lower, if even slightly. I have yet to see any stacked/thickA.F. colas from flowering CMH's (or LEDs) like I do with HPS. I dont want any larf/fluff at all, and it seems that a lot of the bigger plantsI'm seeing grown under 315CMHs stretched fairly tall and have
a great deal of small buds (likely fluffier) on the bottom 50% of the plant.

I'm likely going to get the CMH's regardless, and just make a 4kw veg space. If I decide to bloom the room, maybe I'll swap the lights at that point.

I think theres a great deal of value in having the best of the best plants, from day 1 (mothers/ cutting/ etc), and the only way to tap into that value, is by vegging mothers and clones and teens under the best spectrum of light for vegetating plants. There's a great deal of value to keeping plants shorter/bushier as well. For these reasons, I'll likely get 12 of the CMH's for my room.

I'll likely do a side by side bloom run with HPS/CMH/others if I decide to start blooming the room out.


And thanks to everybody for chiming in =]

 

[Miraculous Meds]

@Natural High- appreciate your insight. I had a feeling that yield/density would be lower, if even slightly. I have yet to see any stacked/thickA.F. colas from flowering CMH's (or LEDs) like I do with HPS. I dont want any larf/fluff at all, and it seems that a lot of the bigger plantsI'm seeing grown under 315CMHs stretched fairly tall and have
a great deal of small buds (likely fluffier) on the bottom 50% of the plant.

I'm likely going to get the CMH's regardless, and just make a 4kw veg space. If I decide to bloom the room, maybe I'll swap the lights at that point.

I think theres a great deal of value in having the best of the best plants, from day 1 (mothers/ cutting/ etc), and the only way to tap into that value, is by vegging mothers and clones and teens under the best spectrum of light for vegetating plants. There's a great deal of value to keeping plants shorter/bushier as well. For these reasons, I'll likely get 12 of the CMH's for my room.

I'll likely do a side by side bloom run with HPS/CMH/others if I decide to start blooming the room out.


And thanks to everybody for chiming in =]

Ive been growing for a lot of years, and I can tell you for sure that the 630cmh can stack as big and tight as hps. Ive used 600w hps for 15 years, and im going to replace them all eventually.


This is not loose and larfy, and not small for a 600w, its a baseball bat.

 

[Phaeton]

... it seems that a lot of the bigger plantsI'm seeing grown under 315CMHs stretched fairly tall and have
a great deal of small buds (likely fluffier) on the bottom 50% of the plant.
I'll likely do a side by side bloom run with HPS/CMH/others if I decide to start blooming the room out.


And thanks to everybody for chiming in =]

During the years of testing one of the parameters researched was position of the lights.

Side by side results showed if 30% of the light was side light the yield (on a total wattage comparison) came in 15% higher for the plants with side lighting.
The current room is just over 5000 watts, of which 1800 watts come from the sides.

Almost all of the extra yield is from the lower buds which traditionally are popcorn.

The overhead lights tested have been MH, CMH, LED, HPS, and fluorescent. Moving a third of the light down to the sides increased yields on all of them.
The fluorescent and HPS were found wanting and are not used as feed lights, although 10% UVB T5's are angled to put 70 microwatts of UVB on the leaves.

This is the eighth year since I quit my day job to be a full time gardener. I do what works and keep good books, I know what pays and what wastes my labor.
Well, not wasted, as all the harvests most definitely wasted me, some take less effort and are more efficient is all.

 

[Jhhnn]

During the years of testing one of the parameters researched was position of the lights.

Side by side results showed if 30% of the light was side light the yield (on a total wattage comparison) came in 15% higher for the plants with side lighting.
The current room is just over 5000 watts, of which 1800 watts come from the sides.

Almost all of the extra yield is from the lower buds which traditionally are popcorn.

The overhead lights tested have been MH, CMH, LED, HPS, and fluorescent. Moving a third of the light down to the sides increased yields on all of them.
The fluorescent and HPS were found wanting and are not used as feed lights, although 10% UVB T5's are angled to put 70 microwatts of UVB on the leaves.

This is the eighth year since I quit my day job to be a full time gardener. I do what works and keep good books, I know what pays and what wastes my labor.
Well, not wasted, as all the harvests most definitely wasted me, some take less effort and are more efficient is all.

I've noticed something similar about side lighting in my own modest grow. My space accommodates 6 plants at most using 5 weeks of veg. We have plant limits of 12 total & only 6 flowering. Sometimes I don't get 6 females from 12 seeds but each plant yields better because light is better able to bounce in from the sides in the flat white 4x4 space. Any grower who isn't bouncing stray light back to the plants isn't getting the full benefit of the power they're paying for.