To SCROG or not to SCROG? LED is the question.
- Thread starter JSB99
- Start date
Danielson999
Well-Known Member
I think because LED's typically have better coverage, especially with no reflectors/lenses, that you end up with better canopy penetration because the light is coming in from more angles. HPS ends up throwing alot more shade because it's so directional. There are dozens of grow journals in RIU of cob growers scrogging with better yields per watt than they got with HPS so it's definitely not losing anything as a bottom line. I think anything it might possibly lose in penetration it more than makes up for by having better distribution, better spectrum and less heat. That's just my observation...
HydoDan
Well-Known Member
Hey man..
If you're doing one plant under a screen I like it..
for multiple plants I found it blocked access when I had a problem plant..
Have a look at this.. see if you get any ideas..
https://www.rollitup.org/t/the-main-lining-thread.542308/
https://www.rollitup.org/t/sixstrings-cob-build.903026/
If you're doing one plant under a screen I like it..
for multiple plants I found it blocked access when I had a problem plant..
Have a look at this.. see if you get any ideas..
https://www.rollitup.org/t/the-main-lining-thread.542308/
https://www.rollitup.org/t/sixstrings-cob-build.903026/
CobKits
Well-Known Member
at what?
JSB99
Well-Known Member
Canopy penetration. That's what I've gathered over the past week from researching.
ttystikk
Well-Known Member
Sooooooooo tell me more about this penetration? It sounds positively pornographic.
Seriously, appropriate illumination at the canopy translates to the whole plant doing well.
LED lighting is best utilised when spread out compared to the point source of HID, leading to superior light distribution and resulting in better yields.
ttystikk
Well-Known Member
But even better results can be achieved with 12-16 chips at 50W or so, evenly spaced across the canopy. All those light sources really distribute the light much more evenly while themselves running more efficiently, and this is why I'd rather work with COBs in this power range than bigger ones.
CobKits
Well-Known Member
i agree. physics dictate that HPS at a distance throwing down the proper PPFD at canopy will "penetrate" deeper at proper intensity, but the sidelighting/array effect from multiple lower cob fixtures offsets this. different effects really. canopies are amazingly complex when you try to apply simple beam physics to an environment ideally packed as full as possible full of vegetation that is absorbing/reflecting wavelengths differently.
JSB99
Well-Known Member
LMAO!
JSB99
Well-Known Member
Very cool! That's the reason I had decided to go with 16 x 1050mA COBs over 12 x 1400mA COBs. Better light distribution with a little less power. I think this equated to 64% efficiency. I love that LEDs have caught up with HPS!
Trippyness
Well-Known Member
LED has surpassed HPS at this point.
ttystikk
Well-Known Member
64% is from running a CXB3590 at 23W, you're still double that, so closer to 56%.
I'm at 60% at 53W only because I'm running my chips colder than the reference test conditions; only 12C!
What he said.
optzulu
Well-Known Member
How ?
You have a warm room with a max temp of 28C and you pump ice cold water in that room. You will have in no time condens.
Show us the build and how you manage to get the cold water to the cobs with no condens.
ttystikk
Well-Known Member
Insulated lines and frame.
MeGaKiLlErMaN
Well-Known Member
Canopy penetration isn't a thing if you scrog... Check my signature and test with a par meter. Yes scrog it, doesnt matter what youre running as a light, you will have an increase unless its a super stretchy strain then maybe tomato cages are a better way to go.
JSB99
Well-Known Member
Actually, I prefer growing them full, with some pruning and topping. I just wasn't sure I could get to the lower branches with the COB LEDs. Sounds like I can. I may scrog again someday. I used to do that. I'm tying to keep my workload at a minimum. I remember scrog being fairly involved.
Rahz
Well-Known Member
Penetration in a scrog is highly dependent on the structure of the plant. If it's Sativa dominant and you get plenty of stretch after the first signs of flowering you won't need to refine the structure, but it could still be helpful. The basic idea is that if your leaf layer is 18" thick and dense you'll get 18" of larf and it won't matter much what kind of light you're using. If your leaf layer below the colas is 4" thick you'll get "penetration" from even a weak light source and good looking flowers all above the leaf layer. When I fired up my first LED and grew under it I didn't do any trimming. I was amazed by the amount of growth. When I cut into those plants and got to where I could see the full dissection I was both amused and bummed out. It looked like I sliced a head of broccoli in half.
Inverse square law- Losses due to reflectance/non-reflectance... that's all it is. If you're growing in an open area there will be losses at the edge. You might design them for higher center readings and lower outer readings (similar to a single HID). You might figure out how to keep the lamps low during flower and easily raise them when needed. You might construct a light barrier around the grow that's easily movable. Keep in mind HID relies on it's reflector for a good percentage of it's output. LED is superior in that regard, but having a more spread out light source takes creative thinking to prevent similar losses from the edge.
If you are working with larger plants and space them out then the plants will be getting side light. If the output is there, the plants will use it. People have found that LEDs have plenty of "penetration" and provide similar yields for less output watts (similar PAR watts) because LEDs are more efficient. This grow reduced the power consumption by well over 1000w and owner was very happy with the results. Unfortunately he didn't post finals, but you can see the distance from the lights and how flower production will be good many feet from the source. https://www.rollitup.org/t/tasty-led-discussion-thread.913304/page-10#post-12906293
Inverse square law- Losses due to reflectance/non-reflectance... that's all it is. If you're growing in an open area there will be losses at the edge. You might design them for higher center readings and lower outer readings (similar to a single HID). You might figure out how to keep the lamps low during flower and easily raise them when needed. You might construct a light barrier around the grow that's easily movable. Keep in mind HID relies on it's reflector for a good percentage of it's output. LED is superior in that regard, but having a more spread out light source takes creative thinking to prevent similar losses from the edge.
If you are working with larger plants and space them out then the plants will be getting side light. If the output is there, the plants will use it. People have found that LEDs have plenty of "penetration" and provide similar yields for less output watts (similar PAR watts) because LEDs are more efficient. This grow reduced the power consumption by well over 1000w and owner was very happy with the results. Unfortunately he didn't post finals, but you can see the distance from the lights and how flower production will be good many feet from the source. https://www.rollitup.org/t/tasty-led-discussion-thread.913304/page-10#post-12906293
ttystikk
Well-Known Member
Not true. Still have to manage LED heat.