It's a trade-off with 80 vs 90CRI. Slightly higher output with 80, and better flowering spectrum with 90. A lot of people are moving towards 90CRI with cobs and strips now.Because you get more than 10% more light out of an 80cri vs 90 using the same amount of electricity. Who doesnt want more light for the same cost?
if your theory was correct you would have seen better growth from the 4k it puts out more light than the 2700k so you kinda proved your own theory wrongBecause you get more than 10% more light out of an 80cri vs 90 using the same amount of electricity. Who doesnt want more light for the same cost?
I thought 90cri would be better when I first got into Cobs but Growmau5 schooled me by showing the data sheets and explaining the difference. You want to focus on intesity first, once to get to proper intensity (800-1000 Par if not using co2) then you can tweak the colors if you want to try and eek out a little more, but most would do that by adding mono leds to the light, like extra 660nm reds. That is getting really nit picky though and 99.9% of people wont care to try and squeek out another 1-2% more yield by playing around with adding monos. Cobs do a mighty fine job all by themselves imo.
I have 90cri 2700k crees and 80cri 3500k Veros on my fixture and the difference in brightness is night and day and PAR readings confirm it for me, but my situation is a little more dramatic due to the different kelvin. I think 3k-4k cobs will work just fine and I doubt there is much of a difference in yield no matter if you pick 3k, 3500k, or 4k to flower with. I have vegged under 2700k and 4k and didnt notice any difference in things like stretch or internodal spacing. The extra light the 80cri will put out over a 90cri light will more than make up for any minor spectral deficiencies.
So with 10 percent more light you got 50 percent more bud that makes your theory hold up even less.....again different color temps so maybe 20 percent diff? I wouldnt call your 2 random grows a test I've seen side by sides that came to the opposite conclusion. If you have a side by side with the same color temp and different cri I would love to see it. Also the chips must be the same brand for the test to be anywhere close to accurateMy first grow was with 90cri Cree 2700k, second with Vero29 80cri 3500k. First harvest = 1lb, second harvest, same electricity, 1.5lb, combined them both, 2.5lb. Very consistent results. Proved my theory right in my grow.
Just making sure this poor guy doesn't take your word as gospel a couple random grows from you shouldnt be a factor in his decisionNot going to debate my results with a keyboard warrior on the internet. LOL. I know what I got, why I got it, and the science behind it. Sorry that you don't.
Oh an this keyboard warrior probably has alot more cob experience than you but I don't try to pass off my grows as a "cri test" to many factors between different growsNot going to debate my results with a keyboard warrior on the internet. LOL. I know what I got, why I got it, and the science behind it. Sorry that you don't.
Id probably do cxm22s or 32s, 90cri 3500k if I was going to build a light, if I was going to do 80cri I would drop down to 3000k.