Input needed for experiment comparing COB LED to HPS DE

Should the HPS plants veg under LED then transfer to the HPS tent?

  • Yes

    Votes: 4 36.4%
  • No

    Votes: 7 63.6%

  • Total voters
    11

CCCmints

Well-Known Member
@CobKits Which luminous COB are you speaking of? I'm thinking of changing my initial test to just the CXM-22 (unless you think luminous has a better COB than that) and the Vero 29 SE. I don't think the CXB3590 will produce results to make up for the increase in cost. So lets say I bought a 2.1a dimmable driver, would I be able to attach a multi-turn potentiometer to that driver and test the Vero 29 and CXM-22 at a different amperage without needing to buy a separate driver for each due to the FV being 51(+/-) for the CXM-22 and FV for Vero 29 being 36.6 (+/-). How limited am I with a standard multi-turn potentiometer? I will definitely be purchasing a good multi-meter (this was also suggested to me on another forum).

I want to order this stuff ASAP but I'm waiting until I know exactly what I'm working with here.
 

ANC

Well-Known Member
if youre using 54A with CXM22, id advise turning the voltage down to just over the max required. that way if you drop a cob youre not sending the rest of the cobs up to 60V which is what teh 54A can do when cranked all the way up

would operate exactly the same for you guys except offer that additional protection
We have had 2 COBs die on us on two banks. One because something got into the fan on its cooler and the other we are not sure of the reason.
The remaining ones on those banks still seem to hold up. But yes, I don't recommend running overvoltage. We got our COBs from you and they are pretty awesome. I think 2 dead out of 42 is not too bad.
 

CobKits

Well-Known Member
I'm thinking of changing my initial test to just the CXM-22 (unless you think luminous has a better COB than that)
there are more efficient cobs but on a price/performance basis the cxm22 seems to be the sweet spot

you can pay twice the price for a CXM32 to get a few more percent efficiency, but it wont gain you much

So lets say I bought a 2.1a dimmable driver, would I be able to attach a multi-turn potentiometer to that driver and test the Vero 29 and CXM-22 at a different amperage without needing to buy a separate driver for each due to the FV being 51(+/-) for the CXM-22 and FV for Vero 29 being 36.6 (+/-).
prob not as single cobs. see minimum voltage for constant current mode on driver datasheet

How limited am I with a standard multi-turn potentiometer?
you can hit all of the range with an potentiometer, but you still need a meter to know where you are at
 

ANC

Well-Known Member
Naah, the other one worked before, I'm pretty sure one of my friends messed it up when they were working on assembling the units.
They had to slap 14 of those 3 COB banks together in very little time, I thought they were more proficient at electronics, but no. They don't belong anywhere near electricity. We are planning another order soon.
 

Hybridway

Well-Known Member
I don't want to veg with MH lights simply because I want to compare LED during the flowering phase vs HPS. I'm trying to show a 750w LED fixture can outperform a 1000w HPS DE in flower, and since I want the experiment to be properly conducted, I want to veg with the same LED fixture then transfer those plants to the flowering tent under HPS.
Thank-you for this. I'll definitely purchase that.
If you truly want to test Hps Vs LED I recommend vegging your hps plants under MH & your led plants under led.
That's what I'm going to do next run as part of my side by side by side journal cuz many folks here have not seen a true side by side from this section in a long time. At least not seen all the way through.
And if testing 2 different technologies then I feel the only real way would be to stick w/ that tech from begining to end.
 
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CCCmints

Well-Known Member
If you truly want to test Hps Vs LED I recommend vegging your hps plants under MH & your led plants under led.
That's what I'm going to do next run as part of my side by side by side journal cuz many folks here have not seen a true side by side from this section in a long time. At least not seen all the way through.
And if testing 2 different technologies then I feel the only real way would be to stick w/ that tech from begining to end.
Your suggestion makes plenty of sense and I've thought about it. I just think the general consensus is HID lighting isn't optimal for veg but its the best for flower. That's why for the initial experiment (there will be many), I want the only difference to be what light the plants are under during 12/12. If I veg all of the plants with the same LED fixture, then flower half of them under HPS and observe the results, then I think we will be able to determine which light flowers better.

Ideally, I'd figure out the best spectrum, maybe mixed spectrum, for vegging with LED and build out that fixture to run against the most popular MH bulb. That's down the line though. I'm going for HPS vs LED initially.
 

Fractured but whole

Well-Known Member
In all of my HPS growing, I have never vegged under HPS. Always MH or CMH. I think taking 2 cuts vegged under the same light, then flowered under each light individual light would be what I would want to see.
 

OneHitDone

Well-Known Member
Your suggestion makes plenty of sense and I've thought about it. I just think the general consensus is HID lighting isn't optimal for veg but its the best for flower. That's why for the initial experiment (there will be many), I want the only difference to be what light the plants are under during 12/12. If I veg all of the plants with the same LED fixture, then flower half of them under HPS and observe the results, then I think we will be able to determine which light flowers better.

Ideally, I'd figure out the best spectrum, maybe mixed spectrum, for vegging with LED and build out that fixture to run against the most popular MH bulb. That's down the line though. I'm going for HPS vs LED initially.
Where do you get your "consensus" info? lol
A hortilux Blue MH (HID) will veg circles around your led's

Now if you want to get technical some will say that growing under one spectrum in veg and then moving to another for flower is stressful to the plants. So I would say you will be giving the upper hand the the plants kept under the led's from start to finish vs the ones moved over to hps
Not sure if your one of those guys trying to do this in a 6 ft tall tent or not but in my area (The "Real" Norcal"), plenty of growers veg under DE HPS

How about take a very uniform batch of clones and put half under each lighting tech for a given period of time, say 4 weeks for a nice round #.
Then flip and report exactly what happens. No additional topping or training to 1 side vs the other or any of that BS. A pure unmolested Biomass competition.
A direct comparison between the two light sources and not grower ability. A top notch grower can steer results to be what they are wanting to see, especially with a little dolled up photography and number manipulation as runs amuck in this section :lol:
 

CCCmints

Well-Known Member
Where do you get your "consensus" info? lol
A hortilux Blue MH (HID) will veg circles around your led's

Now if you want to get technical some will say that growing under one spectrum in veg and then moving to another for flower is stressful to the plants. So I would say you will be giving the upper hand the the plants kept under the led's from start to finish vs the ones moved over to hps
Not sure if your one of those guys trying to do this in a 6 ft tall tent or not but in my area (The "Real" Norcal"), plenty of growers veg under DE HPS

How about take a very uniform batch of clones and put half under each lighting tech for a given period of time, say 4 weeks for a nice round #.
Then flip and report exactly what happens. No additional topping or training to 1 side vs the other or any of that BS. A pure unmolested Biomass competition.
A direct comparison between the two light sources and not grower ability. A top notch grower can steer results to be what they are wanting to see, especially with a little dolled up photography and number manipulation as runs amuck in this section :lol:
Yeah, that's one of the reasons I like LED because they seem to be better suited for full-cycle fixtures. Its definitely a factor people consider when deciding which lighting system they want to use for their grow. I've considered building two LED fixtures (one for veg, one for flower) and purchasing the Hortilux Blue MH bulb as well as the DE HPS bulb. So maybe I could veg 1 tent with the LED veg light and another tent with the Hortilux Blue MH light and then when its time for flower throw an LED fixture with a spectrum favoring flowering in the LED tent and a 1000w DE HPS for the HID tent. Its probably a way better idea comparing LED vs HID instead of LED vs HPS.
Where do you get your "consensus" info? lol
There's really no credible basis for that statement to be real with you. Its just an opinion based on the past 2 months I've been active in the community again.

Thanks for the input @OneHitDone
 

Fractured but whole

Well-Known Member
Yeah, that's one of the reasons I like LED because they seem to be better suited for full-cycle fixtures. Its definitely a factor people consider when deciding which lighting system they want to use for their grow. I've considered building two LED fixtures (one for veg, one for flower) and purchasing the Hortilux Blue MH bulb as well as the DE HPS bulb. So maybe I could veg 1 tent with the LED veg light and another tent with the Hortilux Blue MH light and then when its time for flower throw an LED fixture with a spectrum favoring flowering in the LED tent and a 1000w DE HPS for the HID tent. Its probably a way better idea comparing LED vs HID instead of LED vs HPS.
There's really no credible basis for that statement to be real with you. Its just an opinion based on the past 2 months I've been active in the community again.

Thanks for the input @OneHitDone
you could just get a solis tek mh de bulb and not have to switch out all that equipment
I can't post links yet, but go to solis tek website and check out there de bulbs
 

CCCmints

Well-Known Member
Ok, so this is what I've been looking into doing. I want to have a Quantum Sensor and a Lux Meter connected to a system with software to display the data collected from those meters in real-time throughout the course of the experiment. Think like charts, graphs, numerical values, etc. So I'd like to purchase (2x) Quantum Sensors and (2x) Lux Meters to observe both systems for the entire duration of the experiment. I've already spoken with a software developer about it and he's interested in creating this software. I'm interested in contracting him to produce this software for me to purchase.

I'm also considering building out not only a "LED For Veg" and "LED For Flower" fixture, but also maybe an LED designed for full-cycle, like I originally planned, then just observing that grow without purchasing additional meters. Just see how the same clones from the same hemp plant fair under a "full-cycle light" compared to lights designed specifically for both growth phases.
 

CCCmints

Well-Known Member
im not so sure of that being a consensus

MH vegs like a mofo and HPS works fine too if your strain can take a little stretch
In retrospect, I probably shouldn't have said that. I'm still going to veg the HID tent with MH, probably the Hortilux Blue MH bulb. I need to do more research on spectra from both lighting systems but the experiment is a ways away so we have time to make sure this experiment provides the community with something of value.
 

CobKits

Well-Known Member
Ok, so this is what I've been looking into doing. I want to have a Quantum Sensor and a Lux Meter connected to a system with software to display the data collected from those meters in real-time throughout the course of the experiment. Think like charts, graphs, numerical values, etc. So I'd like to purchase (2x) Quantum Sensors and (2x) Lux Meters to observe both systems for the entire duration of the experiment.
not sure i understand. the LEDs will put out the same PPFD on day 1 as they do a year from now.HID will taper off over first few months then level out somewhat. lux and quantum readings will both show this trend.

what are you looking to demonstrate with that data?
 

CCCmints

Well-Known Member
not sure i understand. the LEDs will put out the same PPFD on day 1 as they do a year from now.HID will taper off over first few months then level out somewhat. lux and quantum readings will both show this trend.

what are you looking to demonstrate with that data?
I was unaware of that. I just assumed LEDs degraded somewhat over a period of 3 months. Then I would just need to purchase 1 Quantum Sensor and 1 Lux meter. Thanks Cob.
 

CobKits

Well-Known Member
I was unaware of that. I just assumed LEDs degraded somewhat over a period of 3 months.
at the currents we run them at they will be 95% as bright as they are now, 10 years from now.

you'll literally be throwing your old chips away for $3 vero gen12s and luminus gen8s in 5 years. and rockin the same meanwells and heatsinks which will have all of their utility in them

the top of the line crees were $60 2 years ago. chips that efficient are now $10
 

nfhiggs

Well-Known Member
In retrospect, I probably shouldn't have said that. I'm still going to veg the HID tent with MH, probably the Hortilux Blue MH bulb. I need to do more research on spectra from both lighting systems but the experiment is a ways away so we have time to make sure this experiment provides the community with something of value.
You said the experiment was going to be about what light flowers them the best. As I suggested, use a MH for vegging, and that takes ALL of the flower lights out of the veg equation, making it a more unbiased test.
 

CCCmints

Well-Known Member
You said the experiment was going to be about what light flowers them the best. As I suggested, use a MH for vegging, and that takes ALL of the flower lights out of the veg equation, making it a more unbiased test.
Yep. I finished out the price list today. Mid next week I'll be ordering everything I need to test a couple COBs individually then I'll build out a 12 COB fixture, purchase all of the equipment for the experiment and get started.

I like this 3D model program you can do some pretty cool stuff with it. It doesn't take too long to learn but you need to learn a bunch of tricks through experience before its a semi-smooth process.

https://3dwarehouse.sketchup.com/model/9fceb8a6-4d07-4ca5-9074-18c2615c5ea0/4x4-12-COB-Fixture
 

deno

Well-Known Member
If your experiment is to test the COBs vs HPS on flowering, the only thing that makes sense is to veg them under identical conditions. Otherwise, the test is invalid.

Post your parts list for your COB build. I'm probably going to build one for next summer, and it would help me a lot.
 
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