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CobKits

CobKits

Well-Known Member
i doubt theyd even rate them in lumens as theyd do so poorly (lumen measurement is green-centric). most monos are rated in mW of flux which you can compare to the mW of electrical consumption. you can do a par measurement on them which would understate PPF as the spectrum favors photosynthetically-active wavelengths

in other words, if youre putting a blurple beside a white led light source, 700 ppfd could equal 800-900 ppfd of white light (just a guess on that ratio, white cobs already mimic the cree curve somewhat (coincidentally and fortunately)
 
BuddyColas

BuddyColas

Well-Known Member
CobKits said:
i doubt theyd even rate them in lumens as theyd do so poorly (lumen measurement is green-centric). most monos are rated in mW of flux which you can compare to the mW of electrical consumption. you can do a par measurement on them which would understate PPF as the spectrum favors photosynthetically-active wavelengths

in other words, if youre putting a blurple beside a white led light source, 700 ppfd could equal 800-900 ppfd of white light (just a guess on that ratio, white cobs already mimic the cree curve somewhat (coincidentally and fortunately)
Click to expand...
https://www.endrich.com/fm/2474/CITIZEN HORTICULTURE COBS FOR PLANT GROWING.pdf
So I found this pdf...and if it's true, they aren't even breaking 100lm/watt. I think the 90 cri citizen cobs would be better and much more efficient...and available.:mrgreen:
 
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BuddyColas

BuddyColas

Well-Known Member
CobKits said:
perfect example

lumens are for humans

plants want PAR
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OK, I respect that. The lumen curve peaks right between their two major peaks. So take the 1818 that you sell. The 1818s put out over 2 ppf/watt (if my calculations are right) whereas the horticulture leds put out 1.6ish ppf/watt. Correct me if I am wrong. Also, the difference between ppf and a-ppf?

FOLLOW-UP:
So A-PPF is "Active PPF" and is measured from 400-510nm and 610-700nm. The Citizen Horticultural Cobs really shine (no pun intended) in the A-PPF spectrum...but so would a cri 90 cob.

This may be beating a dead horse...but this is the Citizen cob thread. Anyway FYI, a 37 watt citizen horticultural cob (CITIZEN CLU04H-40/85-PRB-01) cost $22 usd, compared to a 1212 cri 90 at $13.25 to $14.25.
 
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CobKits

CobKits

Well-Known Member
PPF weights all wavelengths the same between 400 and 700

a-ppf (and ive only ever seen citizen use it) weigts the red and blue spectra

we need to digitize these and put them thru @Ganjineer 's spreadsheet
 
BuddyColas

BuddyColas

Well-Known Member
CobKits said:
PPF weights all wavelengths the same between 400 and 700

a-ppf (and ive only ever seen citizen use it) weigts the red and blue spectra

we need to digitize these and put them thru @Ganjineer 's spreadsheet
Click to expand...
Digitizing SPDs is a stretch for me, but looking at their "Plant White" curve and say the 3500K 90CRI 1818 curve...I'm thinking pretty close...and very available.

And the 1818s look to be about 25% better on the ppf/watt than the "Plant White" cobs.
 
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The Dawg

The Dawg

Well-Known Member
CobKits said:
i asked months ago, theyre not very responsive. it appears to be a very political org where US market has gotten cut out of the horti cobs entirely because were all dopers i guess

currently your LM80 request is on the table
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Horti Cobs We Don't Need No Stinking Horti Cobs bongsmilie

 
pop22

pop22

Well-Known Member
I'm pretty sure that is in reference to "burple" lights. With a white led a lux meter should be reasonably accurate. And for most of us, a cheap lux meter will more than suffice, we're interested in the light spread in our rooms or tents, not to discover technicals specs that have been documented already, thats more of an led hobbyist thing. I got a 50,000 lux meter and it max at the canopy top. Lighting is 1: NLG Mod420 frame with 4, Citizen 1825, powered by 2: HLG240h-C2100b. Light is running at 250 watts at the wall. Just added a Quantum Board running at 117 watts. These are in a 4x4 tent.

Got a couple of Cobkits light engines in another, the 1818 model running at 55 watts each. NICE lights, very versatile! May do a grow in a smaller tent with just the 2 light engines. Using the lux meter will help me get the best coverage I can with just 2 cobs, this is where its useful.


subb said:
Actually I read a bunch of reviews saying if you are measuring LED grow lights this is not the meter you want.. I'll be on the hunt for something that would suit LED better.

Not really sure why exactly but I saw that a few times in the reviews and questions of that meter on Amazon,
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linderstein

linderstein

Well-Known Member
Hi guys , I am confused between cree cxb3070 bin bb 3500k, citi 1212 3500k gen 5 all cri80, some comparison table of these two or by experience which would be the best ?
 
G

GrowUrOwnDank

Well-Known Member
Me thinks that to satisfy customers anymore. Vendors are just gonna have to give shit away for free with free shipping. Hey. It's YOUR fault. For advertising with discount codes and screaming free all the time. Suck it up and deal with it. I guess.
 
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