LED Spectrum Customization Question

[CanadianONE]

Interesting post! I wish I knew what all those values and formulas meant...lol that just shows how bored I'd get studying this stuff...I need a simple formula that works...like percentages...seems I got a lot to learn before I can KNOW for myself what works BEST. I appreciate it nonetheless !

Chlorophyll, the most abundant plant pigment, is most efficient in capturing red and blue light. But accessory pigments such as carotenes and xanthophylls harvest some green light and pass it on to the photosynthetic process, but enough of the green wavelengths are reflected to give leaves their characteristic color.

 

[CanadianONE]

Hmm..that sounds like a huge difference in efficiency and I am interested in DIY LED's....How much do you think it would cost to build the system you described? and does it utilize the "Mcree Curve"? I really am only buying from a manufacturer because I'm looking to get into business....but perhaps I should become a manufacturer seeing as most of the existing companies seem to have little knowledge on the subject. I would like to gain as much knowledge as possible!!! and I appreciate it.

It's hard to say what it would cost because it all depends on your component selection. But it will certainly be cheaper then any manufacturers blurple light and be much more efficient in the process. Have a look as the spectrum chart for the CXA/CXB 3070/3590's in 3000-5000k and you will see they have a great spectrum for what we are all looking to accomplish. I'm sure you could tweak the spectrum a little with some added monos but just on there own they do a mighty fine job and there are plenty of journals on this site that show it.

 

[Meinolf]

Chlorophyll, the most abundant plant pigment, is most efficient in capturing red and blue light. But accessory pigments such as carotenes and xanthophylls harvest some green light and pass it on to the photosynthetic process, but enough of the green wavelengths are reflected to give leaves their characteristic color.View attachment 3494715

You're right.
As far as I recall some charts the green light reflected by an illuminated single leaf (was it our plant?) is approx. ~15% and the green light transmitted is approx ~15% as well. For bushier plants there is a thing called leaf area index that is the ratio of leaf area to ground area, where the total light absorption approximates 1 (0,95 for 4m²/m²).

Besides, is that second graph another in vitro result of single chlorophyll, as the deep dip in the green region is suggesting? Still: "If the quantum yield is measured for the wavelengths at which chlorophyll absorbs light, the values found throughout most of the range are fairly constant, indicating that any photon absorbed by chlorophyll or other pigments is as effective as any other photon in driving photosynthesis." (Taiz et al. 2015: 179).

 

[littlejacob]

Bonjour
So you want to sell pannels that are going to be build in a chinese factory?
If you to make the best one use cxb or Vero's!
And MeanWell driver (hlg...)
Go read one of the manyyy thread on it and see how people's loving their results! And compare the gpw they had before with their hps and now with cxb/vero at equal or even less W
Have a great day ★

 

[unlmtd216]

It's hard to say what it would cost because it all depends on your component selection. But it will certainly be cheaper then any manufacturers blurple light and be much more efficient in the process. Have a look as the spectrum chart for the CXA/CXB 3070/3590's in 3000-5000k and you will see they have a great spectrum for what we are all looking to accomplish. I'm sure you could tweak the spectrum a little with some added monos but just on there own they do a mighty fine job and there are plenty of journals on this site that show it.

I really appreciate the valuable info here...Thank you. I will definitely do a DIY for my own needs.

 

[unlmtd216]

Bonjour
So you want to sell pannels that are going to be build in a chinese factory?
If you to make the best one use cxb or Vero's!
And MeanWell driver (hlg...)
Go read one of the manyyy thread on it and see how people's loving their results! And compare the gpw they had before with their hps and now with cxb/vero at equal or even less W
Have a great day ★

Thank you very much! I will look up those specific models and their reviews. Seems DIY is the way to go. Thank you littlejacob and everyone else who replied. It has helped.

 

[Stephenj37826]

Thank you very much! I will look up those specific models and their reviews. Seems DIY is the way to go. Thank you littlejacob and everyone else who replied. It has helped.

Look up pacific light concepts. DIY efficiency in a commercial package.

 

[stardustsailor]

So would you say HPS defy's science? It sure seams to deliver

Neither I'm saying that HPS bulbs defy science ,neither that they do not deliver...
FGS ! Even green light alone ,can deliver ...

" Under blue and green light we found the most outspoken effects: plants grown under green light were tallest with the largest leaf area whereas plants grown under blue light were shortest, had their stomates widest open, had low leaf temperatures and the lowest total plant weight. "

https://www.wageningenur.nl/en/newsarticle/LED-lighting-in-greenhouse-horticulture.htm

Other things ,I'm implying actually ....
Like that the light attributes quantity ,quality and duration ,actually have a very profound direct way ,
interacting with each other ....

It's quite possible that plenty of light quantity with a " chlorophyll peaks " oriented quality ,
can actually be counter-productive due to long duration ...
As quite possible is the opposite..A lower level of light quantity along with a more "wide-spread" quantity ,
can work wonders under a 12 hour duration ....

Nature is lazy(- will always choose the path of least action),
not open-handed ( - will always choose the path of least energy and matter needed )
and fair ( - will always choose the midpoint/average ,between two opposing extremes .)

Unlikely ,our beloved creations ...
Unlikely our machines ,the term "efficiency " has another meaning for big moma-Nature ...

Cheers.

 

[OneHitDone]

It's quite possible that plenty of light quantity with a " chlorophyll peaks " oriented quality ,
can actually be counter-productive due to long duration ...
As quite possible is the opposite..A lower level of light quantity along with a more "wide-spread" quantity ,
can work wonders under a 12 hour duration ....

Very good information!
I believe that this is the kind of approach that inda-gro is promoting. Not such high ppfd numbers but rather a broad spectrum

 

[OneHitDone]

I'm not sure if this helps ...
Maybe in China still the all-mighty "magic spectrum " remains unknown ...
but for sure ,in Taiwan ,they know plenty more ,than the chinese .......

https://www.google.gr/url?sa=t&rct=j&q=&esrc=s&source=web&cd=42&cad=rja&uact=8&ved=0CB0QFjABOChqFQoTCMey5sL14scCFQZtFAodeNwH-Q&url=http://www.mdpi.com/1996-1944/8/8/5240/pdf&usg=AFQjCNFqudWbItH66ZYJLt6UvFMJZZ_WyQ&bvm=bv.102022582,d.d24
.....
Althought the phrase
" Although the use of artificial light such as torch light to trigger an early
blossom had been reported in ancient China nearly a thousand years ago ..."
Makes you wonder ....



* photosynthetic action spectrum resemblance (SRPAS)
photosynthetic action spectrum (PAS)

( ...) It is noteworthy that plants do absorb green light to some significant
extent, e.g., the absorption of green emissions at 555 nm, for example, is 26% of the peak absorption in
the PAS. Furthermore, the energy absorbed in the green light region, i.e., from 495 to 570 nm, measures
17% of the total energy absorbed by the photosynthetic action spectrum. This implies that the green
light-dominant mid-wavelength emission is not to be ignored in plant growth [48].


The high spectral resemblance may be attributed to the employment of a twin-peak blue emitter
thatnerates two broad-bands covering the short- to mid-wavelength regions, and the employment of a
diffused mono-peak red emitter that generates a relatively wide broad-band extending from the mid- to
long-wavelength regions. In addition, an over-90% spectrum resemblance can also be obtainable,
provided a deeper red emitter is incorporated, as shown in Figure 3b.
It is interesting to find that the typical LED lamps (Figure 4a) show a SRPAS higher than that of the
plant growth-specific LED. That is because the light sources of the former emit a broad band of light
ranging from 470 to at least 780 nm and, hence, a much wider overlap with the PAS results in the
mid-wavelength region, although the overlap is somewhat lower in the red emission.
To improve on this, the inclusion of more red and blue emissions are suggested in typical white LED
lamps. For example, the SRPAS can be increased from 60% to 91% as two additional blue and red LEDs
peaking at the vicinity of the respective absorption peaks of the PAS are employed. (Figure 4b).
(....)


So ...
These folks seem to know pretty much their shit ,ehh?
..... they seem to know ,oh yeah ......
How come in China you did not .?
?
The 80's are over,mate ...
History .Gone ...
For good ...

.....
425nm x3
445nm x9
450nm x6
475nm x4
480nm x4
640nm x7
660nm x14
675nm x7
730n x2
6500k x2

12000k x2 (<==== !!!! Ain't that known also as "blue " ? )
>Oh my ....My Gawd ....
...
Wher's the dried frog leggiess and the worm-spit tincture ?
Without them ,yain't gonna be doin' anythin' right ,son ...

Better yet ,trust the Taiwanese ...
They seem to know ,much better ...

Is there an led light available on the market with that recipe?

 

[BM9AGS]

Interesting post! I wish I knew what all those values and formulas meant...lol that just shows how bored I'd get studying this stuff...I need a simple formula that works...like percentages...seems I got a lot to learn before I can KNOW for myself what works BEST. I appreciate it nonetheless !

Learn the efficiency percentages of the diodes you're looking to use!
Then see what Osram SSL80 latest gen are. Understand that if you're pushing near fluorescent or hid efficiency you're just another paperweight Mars-equivalent company.
Then see how much money you're willing to spend on employees who will spam horticulture forums with egregious information if you're it lights are not better than fluorescent.
Understand that California light works and BML horticulture use only Osram Oslon SSL80 last gen LEDs

Now take a small word of advice that if you are not using top bin Cree cobs CXB series you're wasting your time and ours.

And good luck

 

[captainmorgan]

A big problem with using many different LED bands is finding the right ratio and the proper distance for the light to mix properly. The only thing I would consider mixing is 5000k range with reds. COB's are killing it right now,all by themselves so I wouldn't recommend someone new to LED to try mixing spectrum's.