URSA LED
Well-Known Member
Hey stardustsailor,
Great info! Just what we've been looking for.
Just a heads up, the Duet 2400 was designed for plant grow in general (not specifically for cannabis), however we may decide to run with a white light with 660nm depending on market reaction.
We'll have a better idea after hempcon.
Our research team including me will be going through this data today.
Great info! Just what we've been looking for.
Just a heads up, the Duet 2400 was designed for plant grow in general (not specifically for cannabis), however we may decide to run with a white light with 660nm depending on market reaction.
We'll have a better idea after hempcon.
Our research team including me will be going through this data today.
Thank ,once again ,for your answers .
The question is like that- ( rephrased ) :
Why 552.4 umols/sec of the ( red nitride ? ) phosphor output ( broadband 660 nm ) versus
1036,2 umols/sec of the 455 nm chips output ?
For most plants it should be the other way around ..
(Duet 2400 @ 6A )
- Why would anyone want to use white light to grow marijuana?
( Quick answer ? Cause white light grows plants ,better than any monochromatic combination .... Real Life Field tested 101% ! )
For quite a few reasons,to be more precise :
a ) Firstly to check upon plants for under or over fertilisation , pathogens and/or other plant health issues .
White light helps our vision ,for doing so ..
Furthermore white light makes a nice and relaxed "environment " for human vision ,
when attending the garden ...
b ) Green wavelengths serve as a "slow down " signal to the photosynthetic systems .
Very useful ,when growing under ( of non- variable characteristics ) artificial lighting,
for 12 hours or more .
Nobody wants oversaturated & exhausted chloroplasts .
c ) " The absorption level for green is extremely low on plants " ...
Rather false statement ,I should say ,If I may be excused ...
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Lower than blue and red wavelengths yes ,but not " extremely low " .
Extremely low is the absorption over ~730 nm .
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Furthermore ,the " Relative Quantum Efficiency " of green wls ,
is actually higher than of blue ones ...
( As also RQE of 600-620 nm amber-red wls is higher than of 660 nm )
d ) "Green window " ...Quite a few folks ,like to call it " light penetration " ..
As blue & red wls ,tend to be readily absorbed by the top layer foliage ,
something has to be "left " for the lower parts of canopy ,to be "fed "...
That "something " is the green and yellow wls ,that are being transmitted through the top layer leaves to the underlying leaves ...
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During the early era of LED growing ,many had pointed out that "LEDS lack penetration " ,
when compared with the "trad" HIDs ...
HIDs do emit a good amount of green and yellow wls ..(power-wise )
Blue and Red monochromatic LEDs do not ...
Thus ,they lack ....penetration ..
( ...Damn ,those Kevlar-reinforced leaves ....... )
e ) Blue wls output should not be more than 10-20% of the total output ,in power terms ...
(photobleaching & photoinhibition await somewhere around here ...check question #2 )
Cool white ( phosphor converted ) ,can easily provide the blue wls needed (in power terms ),
plus it also supplies the plants with the VERY useful green and amber wls ..
.....
Hope I was helpful...
More info > here < .
( You should consider hiring an experienced grower as an advisor ...
LOL!
Me for example ...... )
Cheers.
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