mon·o·chro·mat·ic
ˌmänōkrəˈmadik/
adjective
- containing or using only one color.
"monochromatic light"
- PHYSICS
(of light or other radiation) of a single wavelength or frequency.
Monos are entirely different beasts to cobs hybrid, you're talking about epistar reds, blues, greens, cyan, orange... strict nanometer ranges within +-10nm of its primary wavelength. Cobs vs smaller white emitters (xpg, xpl, xmls, mkr) are a realistic/usable comparison and again, just a quick characterization lookup showed the xpg2 (dono the specific cct, assuming best case scenario) to be within 12 lm/w of a 3590.
Hang on and I'll edit and reply to the rest:
"So would you agree then that if one light source gives off the same light output then another that w/ the same heat output that they'd both be the same efficiency?"
Yea that's exactly it, if they are BOTH producing say 4.8 joules/w and whatever BTUs of heat, they are equal in efficiency. And would perform similarly AS LONG AS the spectrums are similar enough. Can't take 1:5 red blue and stack it against a 80 cri white and expect great things just cus they're equal in efficiency.
"So, if one light source (A)= in efficiency (umol/joule) puts out 1/4 # less then the other light source (B) consistently (yield/joule) with identical side by side comparisons, but their both rated the same Efficiency in umol/joule. So my Freind. I ask you now, which light is most efficient to you?"
Your wording on this is a little iffy but I'll do my best here, let me know if I'm not understanding and maybe we can bridge a gap or somethin.
If you are stating both lights are equal in efficiency, but a 25% difference in results- the only way yield would fall off is bad choice of spectra (broad difference between the two, say 6500k vs 2700k for examples sake), over saturation, nute/environment etc like I've said before.
If the lights are identical spectrum and efficiency, just different output (literal drawn watts, not umol/w, ex. 400 vs 600w) then yes varied dry weights a given as a whole, but when you figure your g/w between the two you should be able to see the similarities (given each light is fit for the space they're in) and come out very close.
But typically with a wattage difference though comes an efficiency difference unless you overbuild/run more leds at lower power for the larger draw light to ensure equal efficiency.
Data sheets are not golden, but they are literally our best source for information until we start measuring with our own multi meters, and are a great way to intuitively pick your best option. And cree is one of the more reliable ones with their binning system whereas bridgelux could have a wider variety between chips of similar specs
Edit I'm not some demigod of leds, the people here that helped me understand what I do today- please chime in and correct me if I fugged up anywhere, but I do feel confident in my understanding to hopefully help others understand. The electrical part is coming together but basic shit as of right now... cannot wait for the PLC class!