LED Comparisons

[BigJer]

I will say this after my first harvest for this year, I was also testing different LED's types (COB vs SMD) mainly to bust the myth by using a visual and numerical comparisons was to use the COB full spectrum light fixture VS the SMD light fixture. I have also done this to show that needing 1500 dollar plus fixture to grow a plant indoor is BS. No names as most of all these companies use the same, YES THE SAME BRAND, LED's.

The COB (300 watts x 2) I can adjust the spectrum to any thing I want but used the factory preset for vegetation and the SMD (SMD 400 watts x 2) is designed for vegetation. I used the vegetation mode on the controllable light so the test could be as fair as possible. 18/6 lighting schedule over 5 weeks.



My perspective:

LED Comparison: COB fixture has 18 LED's and the SMD fixture has 720 LED's (Per fixture)

Coverage Advantage: They both covered said coverage area but the SMD edge is a sharp coverage area where the COB was not as sharp but has reflectors around each COB LED could be causing that.

Growth Comparison: COB: 18- 24" Actual growth from each light fixture covers 3x3 area in 2x4 tent. Even mix on sizes but less plants (6 total).

SMD: 18-24" Actual growth each light fixture covers 2x4 area on open air 2x8 table. However most plants grew (16 total) closer to 24".

Power Consumption: COB fixture 120VAC x 2 $50 per month
SMD fixture 120VAC x 2 $50 per month


All plants were seeded the same day and include 8 different strains in 3 gallon pots using indoor potting soil mixed with coco and large perlite.

Growing in the open room versus climate control tent? Open room really surprised me. The temperature in the room is more stable all day (68) versus 75-80 in the tent but growth was overall better in the open cooler temperatures. I have also read on line that plants like cold water for feeding. Foliage growth better in open area as well.

I will have comparison scientific numbers soon for the vegetation phase with flower soon to follow as I move plants around. Flower will have 1000 watt COB full spectrum x 2 with no adjustability versus 4 x 500 watt COB LED fixtures with adjustability.

The COB LED is the winner for me in the long run. It had much better edge growth (both fixtures comparable on growth), half the size of the SMD fixture, fully adjustable spectrum (Many fixture companies offer this on many fixtures now) from seedling to harvest. Full spectrum LED's are the closest thing to replicating the sun on the market but there are other full spectrum LED's other than COB. Both fixtures are voltage switching so run them on 220 VAC if possible to keep power bill down.

 

[WeedHopper]

Interesting read my friend. So what and whos Light System do you recommend for growing from start to finish?

 

[BigJer]

Interesting read my friend. So what and whos Light System do you recommend for growing from start to finish?

I think it's NOT a name brand issue versus quality of parts used issue. A lot of different companies use the same quality LED's but why is one $600 and one $1500 for virtually the same specs. As of last night, now I have had plants vegging under 2 different led style lights, the plants under the less expensive SMD style exploded under the week 4 feeding schedule versus the COB style BUT one set of lights are in the open the other in the tent. Open area with less environmental control is doing better. I am getting ready to put 30 more into flower in 3 to 4 days and I will answer that question about better.

 

[WeedHopper]

I have actually grown several time in an open room situation verses a closed room and my plants loved it. I substituted side lights to make up for reflection from a closed area with Mylar or whatever.

 

[BigJer]

I have actually grown several time in an open room situation verses a closed room and my plants loved it. I substituted side lights to make up for reflection from a closed area with Mylar or whatever.

That's funny you say that about side lighting. I moved mine out a bit wider and angled them to expose the sides to good light as well. It made a big difference on the lower outside of plant bud size and growth. At this point Panda Plastic or Mylar could be in trouble!! Kinda like that $1700 paint care and upholstery kit the car dealer says you need. My PAR meter will give me the answers!!

 

[WeedHopper]

Yep. A little side lights goes along ways and is much better then reflection. That's simple logic.

 

[BigJer]

Ready for this boys and girls? I have plants reaching across to the other table's lights that are angled versus flat and just above it. Pictures and explanations to come.

 

[ROSTERMAN]

Ready for this boys and girls? I have plants reaching across to the other table's lights that are angled versus flat and just above it. Pictures and explanations to come.

Roster LOVES Pics

 

[BigJer]

Ok the experiment is done, as in done done, and this is my perception of said experiment.

First part of the test was in the seedling, clone stage using 18/6 veg cycle. I used a MCOB fixture and the SMD fixture. SMD is designed for vegetation and the MCOB is a tunable full spectrum. MCOB (16 LEDs 300w EA) X 2 in a environmentally controlled grow tent the SMD (720 LEDs 400w EA) X 2 in a open space with just the air in the open room. This one really surprised me. The SMD's blew away the MCOB's like they were off. Within four weeks in tent and on tables I shut the tent done. Anyone looking for a seedling tent? After 4 weeks all the plants were between 24 and 30 inches and the ones from the tent half that size. I moved them to the flower room.

During the shift to the flower stage I let the 18/6 schedule go for the next part of the stage for 4 weeks.

The big full spectrum COB 16 LED 1000w each X 2 versus the controllable full spectrum MCOB 18 LED 600w each X 4. The COB prompted a big growth spurt while the MCOB grew but half as fast. First trim the both looked like cats that got washed but it's for science right? That's where the difference really showed. I had the MCOB lights set to vegetation and the COB are all preset full spectrum. The table is a 4x8 table. I had branches from the COB table reaching across to the MCOB!!! The plants grew so fast on the COB table I had to set them in a tray on the floor but, very thin a no fill out however on the MCOB table the plants were exploding. Bushy, full, very green (Both tables looked healthy).

Last Friday I moved them to the flower room and 7 days later everything flowered so the weights will be the final tally but at this point I am betting on the MCOB. Pictures to come once edited with explanations.

 

[BigJer]

Ok guys 2 days ago i had this huge write up going and took my mouse and closed my browser. IF ANYONE has a question about lighting and how it works? Take a great opportunity to see how LED's and the light spectrum work. I will show my proof, that I had before I found this, matches plus some insights from my experiment notes. ENJOY

 

[WeedHopper]

Great teacher in that video. I didnt finish but i will.

 

[BigJer]

Finally eye candy!! So I know all the lights are the same now. I had to pull the two 1000w fixed out put because the plants were growing past them but with little flowering. All pics have captions. I will start a new thread on the findings and I am calling out the LED market. That's is right, calling BS on them. If they don't have a way to control veg and flower, don't buy it.