In most parts you find me ,agreeing all along ...
Just a note though....
"Oslon CC is an high IRC led, 95CRI, that means very high cyan/green/yellow in the spectrum. The 2700K KR is 89lm @25°C @350mA, the 4000K KT is 104lm @25°C @350mA, certainly the spectrum will be very vast, but a lot of energy will go to cyan/green/yellow photons, and those wavelength are only useful for our plants when the light intensity is very high (as for HPS), because at high intensity the photons can cross the leaf and be used."
Actually,yes it goes like this ....But still even in lower intensities ,all photons in range ~350~750 nm are utilised by plants ....Higher intensities offer "the green window " for lower parts of plants to "flourish "
...
"So at present i think that if we use high green/yellow light, it must be with very efficient emitters (HPS has high yellow content in spectrum and plants use it for flowering, HPS 600W is around 160lm/W). And personally i think that OSLON CC has not enough efficiency."
Well ...Now here things are more complicated than that .....
In fact Oslons ( the Warm White ones ),are
more efficient than the average HPS ....
Let me explain ....
It is wrong (totally wrong ! ) to use the " lumens " unit ,so to calculate efficiency ....
Once again ,this is a photometric unit ,totally irrelevant and " alien " for controlled environment horticulture ..
This unit is directly related to human vision sensitivity/perception of "brightness" and of course spectrum of light ....
Human eye perceives 1000mW ( radiometric power ) of green light at ~555 nm ,as 683 lumens .
Now ...If a white phosphor led ( a warm white one ,for example ) does not have a lot of Cyan/green/yellow wls in it ..
And emits a bit of light over the 700 nm mark (invisible to us ...) ....
..Of course it is going to be of i.e .
......89lm @25°C @350mA....
But that doesn't mean the led is not efficient ....
In fact ,radiometrically ( Watts ) it might be more efficient than a hps of 160lm / Watt ....
( HPS has lots of green / yellow wls ....So it appears much "brighter " light to human vision ....)
But hps for every electrical Watt ,only ~ 30% is turned into light power ...( ~ 300m W ) ....
Unfortunately ,is not easy to obtain accurate radiometric output values for white leds ....
They are made to serve human vision ,so usual efficiency unit used, is
lm/Watt ...
But for horticultural purposes,simply , it does not mean absolutely $hit !
....
So ,taking into account :
-Today's specialised phosphors for leds ,with high convesion efficiency ( >95% )
-Thin film led dies/chips
-High efficiency Chip Level Conversion ..
Then ,one can assume ,that if an average blue die of 500mW output ( 50% radiometric efficiency ) ,
is used to make a Warm white Oslon ....
And pretty roughly , the losses from phosphor conversion are about ~20 % .....
Then radiometric output power of a WW oslon should be around ~400 mW .....
That is 40% efficiency ....
A whopping 10% more than average HPS ....
So at 89 lm /Watt ,an Oslon WW led ,is 10% more efficient at producing light ,than the average HPS of 160 lm /Watt ...
And no ....
High CRI WW ,seriously ,do not have great amounts of Cyan & Green..
Mainly reds at ~620 ~ 640 nm .....
nm Rel.Power multiplier
600.0000 0.7662
603.0000 0.7954
606.0000 0.8251
609.0000 0.8545
612.0000 0.8829
615.0000 0.9093
618.0000 0.9335
621.0000 0.9547
624.0000 0.9731
627.0000 0.9870
630.0000 0.9966
633.0000* 1.0000 *(peak of WW 2700 K )
636.0000 0.9984
639.0000 0.9907
642.0000 0.9783
645.0000 0.9607
648.0000 0.9394
651.0000 0.9142
654.0000 0.8864
657.0000 0.8555
660.0000 0.8225
663.0000 0.7871
666.0000 0.7503
669.0000 0.7124
672.0000 0.6742
675.0000 0.6359
Neutral whites of high CRI ( ColorChamp ) ,yes ,they do have higher amounts of Cyan/Green...
...Lumens ,are not a unit ,to judge ,a led's efficiency ,for growing ....
By far ,the wrong unit .....
Neither it can be used to "compare" even of same temperature leds ..
Slight differences at their spectrum ,can result in great differences at their lumen output ..
So in fact a i.e NW led #1 can be of 100 lm/Watt efficiency and another NW #2
( even of same Kelvin Temp ....) can be of 80 lm /Watt ...
And actually the latter ,to be more powerful than the first ..
....
In radiometric terms ....
(What is really important for us ,led growers ... )
As the first might have more rel. power in green wls and/or
the second might have a bit more reds or far reds in it's light ...
.....
Brother Guod ,has a nice design going on ....
Covering the Blue/Red photosynthesis " needs ",with high efficient blue/red leds ...
And at same time covering "auxiliary " pigment peaks -and creating white light at same time- by using
the complementary colors of Blue & Red ...
Amber & Cyan ,respectively ....
Keeping overall efficiency as high ,as possible ...
Future ,seems really exciting ,for our led growing world ...
Keep up your great work ,brother ..
I'll be following all along ....