LEDgardener

Hey guys, hoping there are some folks here who dabble with light recipes and cobs.

I'm interested in adding some far red 3w diodes to my fixtures.

Does anyone know if you need whole coverage of the area ( 8 x 4 ) or would 2 small rails be enough to put the signal out there ?

Also what driver would you recommend for say 4 x 3w diodes. I'd make 2 of them for each array.

Any tips or advice greatly appreciated.

I am using 10w 730nm cob in a 2x2 tent and that should be more than enough

Huktonponics wrote: ↑

Tue Feb 20, 2018 2:15 am

Hey guys, hoping there are some folks here who dabble with light recipes and cobs.

I'm interested in adding some far red 3w diodes to my fixtures.

Does anyone know if you need whole coverage of the area ( 8 x 4 ) or would 2 small rails be enough to put the signal out there ?

Also what driver would you recommend for say 4 x 3w diodes. I'd make 2 of them for each array.

Any tips or advice greatly appreciated.

I somehow missed this. adding color for what would be my main question...

are you thinking of adding 660nm red to boost the cobs? adding 730nm to put them to sleep quicker? or combining the two for Emerson effect with still having them on separate channels so you can still have 660nm to wake them up and 730nm to put them to sleep maybe with future uv low nm blue later on.

this is some dumb luck I was going to link a driver from RapidLED to use with monos and found and new product I haven't seen yet...
https://www.rapidled.com/emerson-effect-booster-board/
exactly what I was talking about!!!! right there they give specs for each of those to cover a 2x4 area.. so your 8x8 would need 4. but it also tells you how many of each to use for 2x4 are! ( it's 2/1 660nm/730nm 18 total roughly 30watts)

the easiest way to power multiple monos or board like that and have individual channel/color control is dc/dc drivers. something like this https://www.rapidled.com/mean-well-lrs-350-36/
wired to these little guys( there's 2 in their kit. 1 for 660 channel 1 for 730 ) https://www.rapidled.com/mean-well-ldd- ... le-driver/ thru a board like this https://www.rapidled.com/ldd-h-4s-driver-board/ to each channel of monos.

to control those independently a storm X is a good choice. https://www.rapidled.com/coralux-storm- ... ontroller/

I'm sure it's cheap digging all of the parts yourself but that should give ya a good clue where to start.

Hey

I was just thinking about this emmerson effect strip from rapidled. But i wonder, why those 660nm leds?
Don't we already got red in our spectrums?
Also, do u still believe that emmerson effect is gonna enhance your grow?
Do u know this is based on photosynthetic activity equilibrum between PSII and PSI? In most white lights with a decent photon flux, both are already ativated at high rate and emmerson effect is not availible anymore. It also has been shown by basical experimentations.
emmerson effect is mostly usefull for red/blue high ratio spectrums to compensate photosynthetic efficiency comparing to a white light. Spectrums that already need 730nm for physiological reasons more than anything.
730nm are still very important for physiological aspects. But wether emmerson effect is availible or not, since we already got PSII activation in any spectrum, what's the point with the red?

again I'm glad you joined!!!! welcome by the way to the forum

I'm just a noob to this and I'm already picking up from you... I had no clue about the "photosynthetic activity equilibrum between PSII and PSI".. so basically ( if I understand correctly) if you run a good white diode, you got what you need? the additional 660/730 would be more beneficial for cheap Blurple lights?

since we do have some red in our 80cri chips.. would the bump in the 90cri make much of a difference? along with adding some 730? what ratios work well together?

I'm just a k.I.s.s. type of guy.. and run on common sense... everything you said sort of made sense to simple minded me and I'm glad we now have a spectrum guru hanging out with us!!!

Jolly Green Giant wrote: ↑

Tue Mar 20, 2018 6:08 pm

again I'm glad you joined!!!! welcome by the way to the forum

I'm just a noob to this and I'm already picking up from you... I had no clue about the "photosynthetic activity equilibrum between PSII and PSI".. so basically ( if I understand correctly) if you run a good white diode, you got what you need? the additional 660/730 would be more beneficial for cheap Blurple lights?

since we do have some red in our 80cri chips.. would the bump in the 90cri make much of a difference? along with adding some 730? what ratios work well together?

I'm just a k.I.s.s. type of guy.. and run on common sense... everything you said sort of made sense to simple minded me and I'm glad we now have a spectrum guru hanging out with us!!!

Hi,
Thx for welcoming ^^
I think you ask the good questions, but i can't answer all. I've been trying a lot of spectrums but there are so much more to do.
White diodes and precisely warm white got a very wide spectrum. Cool white (80CRI or lower) led spectrums didn't show a good efficiency at growing plants in most cases even not talking about flowering. I prefer using warm white and adding blue if needed, the red/far-red part is really important.
So "if u run a good white diode you got what you need", well there are a lot of different white led spectrums that i'm sure are very good but the question is: According to what you want to do, what one is gonna be the good one?
Switching from 80CRI to 90CRI implies way more red and far red, so to be sure on the result if not just trying, the only way is to calculate physiological parameters. Actually i got an idea, and i can calculate some parameters but i got not the miracle answer. If u ask me for specific conditions i can give you my opinion and some infos ofc.

Concerning this equilibrum between PSI and PSII, it's going over emerson effect, involving photoinhibition and photoprotection process and even more. Actually I can't tell if a warm white led is optimized regarding to this parameter. I'm still investigating a means to calculate the effective rate and got some clues.

But this applies to the every parameters. Of course, a supplementary 730nm would be way more usefull on a red/blue spectrum than on a warm white led. But it doesn't means that it is totally useless for the white.
I'm always looking for optimisation, but what does really matter for me, once you basically know how to do a decent spectrum, is pointing out what is really usefull and what is just marketing.
And i think that's what is Emerson effect, a very interesting scientific discovery leading on photosynthetical centers knowledge, but used by sellers as a marketing argument. Exactly like the pigments' absorbance spectrums, a very important scientific information that doesn't help you to make your spectrum any better.

A very good article experimenting emmerson effect quote:

"The involvement of PSI in the FRIFS* phenomenon
as a factor limiting the non-cyclic electron transport is
clearly confirmed by the fact, that in our experiments
FRIFS has a lower value when the fluorescence was
excited by red modulated light instead blue light
(FRIFS = 2.5% under 640 nm light and 11.8% under
470 nm light-both at 0.1 μmol photons m–2 s–1). It should
be noticed here, that blue light at 470 nm preferentially
excites PSII, whereas 620-640 nm light excites both
photosystems nearly equally (Hogewoning et al., 2012)."

*FRIFS: Far-red induced fluorescence shift (decrease). In this case, the fluorescence decrease means the energy is preferentially going to photochemical réactions, thus photosynthesis. (so FRIFS=Enhancement, in this study)

Far-Red Spectrum of Second Emerson Effect: A Study Using
Dual-Wavelength Pulse Amplitude Modulation Fluorometry
V.S. Lysenko, V. Varduny, E.I. Simonovich, and al

It seems blue is even more efficient at emerson effect than red.
At the end, if we want to balance the activity of PSI and PSII, by activating PSI with 730nm, why would we add any other colour to also activate PSII? It got no sens anymore.

I had to read thru it a few times but I'm getting it

when I started looking into DIY and LEDs I had no clue what I was doing spectrum wise.. I had no problem with the math figuring what works with what and how efficient etc etc... but those rollercoaster rides of charts didn't mean much to me.... knowing I was going to veg and flower under the same light, I chose 3500k quantum boards as my base. based on hearing 4k for veg.. 3k for flower... "hell why not go in between when doing both" was my k.I.s.s. logic. I also liked that it had a good blue spike to go with the red spike.... turns out I absolutely love what they are doing for me! I have yet to flower under a 3000 or 2700.. but I have done 4000k... I still prefer my 3500k over just 4000k.

another reason I picked 3500k was hearing that more blue nm range durning flower could enhance flavors and smells.. I'm guessing it's true... at lease compared to my old hps I noticed better flavor in my flower for sure.. but don't know what that would compare to different spectrum LED.

I do have 1 question... 730nm aids them to go to sleep faster at the end of the light cycle correct? which nm range is it that wakes them up quicker?? I thought morning sunrise was heavier in the 630-660 range.. but I've seen people say it's the 730nm just like putting them to sleep.. that confused me...

I'll definitely be asking more specific questions in the future

For grow+bloom i'm using 3000k but this is very personal. It depends on a lot of parameters. What i can say for sure is it lacks of blue for the first 1-2week so i need to use more powerfull lights than other would. Most of the time i got blue leds so anyway.
I'm going to try 2000k new bridgelux vero on a friend's setup soon. Adding 450nm when it is needed. I've been hesitating a lot between this 2000k 65CRI and a 2700k 90 CRI. I'm really curious of the results

The 730nm at night, for short day plants it's effectively acting as a sleep (sleep faster to be precise)signal. It's due to the phytochromes interactions with the circadian clock regulator :Constans (CO). As the 730nm signal desactivate a part of the phytochromes.

Concerning the morning, the phytochrome activation would be the wake-up signal. All visible part of the spectrum is activating the phytochromes but not at the same rate. The most active range is around 650-660nm.
But i'm not sure it's a good idea to wake up ur plants fast If we are still considering a short day plant on the flowering part.
I've been investigating flowering induction in short day plants for a while, specially phytochromes interactions with the flowering locus.

The phytochromes interact in differents ways with this flowering gene, but here we are interested into the circadian clock related interactions again:
If i remember well the CO accumulation allow the flowering locus to express signalling, But the active form of phytochromes repress CO accumulation. That's why CO quantity is reaching a max only at the end of the night when the phytochromes are back to the inactive state. When comes the morning, the CO quantity is going down for maybe 2hours (don't remember exactly) before it reach the lowest point that is gonna be stationnary (almost) till the nightfall.
So, what i mean is: This slow wake-up is probably helping flowering to occur faster as the CO quantity is still high for some times. As far as i dig in the scientific way, it's still the same shiit, a longer night for a faster-stronger flowering induction. So it's usefull to sleep faster, but if u wake ur plant up faster, you are shortening the night in a way.
So the 730nm wake up isn't such a bad idea, it's not as usefull as the same treatment at night but at least it's better than going full 660nm at the 1st second of the morning.

Do you do lectures?? I would be in the front row!!!! again taking a few times reading thru to understand it.. but it makes sense, kind of like how I'm never instantly awake first thing in the morning.. it takes awhile.. especially when I use my personal 730nm ( lol I take cbd capsules for insomnia about a hour before I want to pass out) to help me go to sleep faster.

I love that I can take your "way over my head" scientific answer and use common sense so I can relate to what your saying . you explain things well... at lease I'm starting to get it.

cheers

Very nice read

I was thinking that the Red from my 3000K QB288's should be sufficient combined with some Far Red.

So have anybody done a Far Red build? and is it worthwhile, or should we just buy something like the Far Red puck?

What about adding blue and UV-A at certain points in the cycle?

What would be the ultimate spectrum tweak to add to a white light setup?