Adding deep & far reds to Quantum Board build

[Ginger Viking]

I'm using more or less the same but I've added far-red is only for end of day threatment(6 XP-E's, only 3,5w net., for 5-10min. at lights out). Too much far-red cause unwanted stretch and in the worst case SAS(shade avoidance syndrom). The correct amount of far-red is difficult to determine. For this reason I mix CRI80 strips with CRI90 COB's, because CRI90 COB's has already shown that it works very well with its increased far-red part.

That's my latest build..
https://www.rollitup.org/t/led-users-unite.240615/page-466

What is the what is the suggest watts per sq ft for UVB then and lighting protocol for it? Goes to show how little I've looked into

I'm using more or less the same but I've added far-red is only for end of day threatment(6 XP-E's, only 3,5w net., for 5-10min. at lights out). Too much far-red cause unwanted stretch and in the worst case SAS(shade avoidance syndrom). The correct amount of far-red is difficult to determine. For this reason I mix CRI80 strips with CRI90 COB's, because CRI90 COB's has already shown that it works very well with its increased far-red part.

That's my latest build..
https://www.rollitup.org/t/led-users-unite.240615/page-466

What is the protocol for UVB? watts per sq ft, when to use during light cycle, and duration?

 

[Randomblame]

What is the what is the suggest watts per sq ft for UVB then and lighting protocol for it? Goes to show how little I've looked into

What is the protocol for UVB? watts per sq ft, when to use during light cycle, and duration?

A 3ft. or 4ft. tube per 2x 4' is okay, thats 39 or 54w! Start when switching to flower circle with one hour at noon and increase slowly to max. 3h per day from flower day 30.
For effective UVB radiation use them 12-20" above the canopy. Burned tips and leaf margins are first signs of too much UV. And you only need UV in the flower circle.
These tubes, when used properly, contribute to plant health by stimulating antioxidants which protects the cells.

 

[tazztone]

i read that UVB is detrimental and we should use UVA instead.
https://www.blackdogled.com/blogwhich-is-better-uva-or-uvb/

 

[Randomblame]

i read that UVB is detrimental and we should use UVA instead.
https://www.blackdogled.com/blogwhich-is-better-uva-or-uvb/

But it is the UVB radiation that significantly prolongs the active ingredients. UVA will only change / improve the terpene profiles, antioxidants and so on, but the effect on the active ingredients is not that strong as they claim. The reason for their claim could be that UVA diodes are widely available but UVB is not. Today there are very few UVB diodes and they are expensive and not powerful enough.
If plants eg. grow at 2000m, UVA and UVB levels are increased, not only UVA. The same applies to equator height, since the distance to the sun is also reduced.
In fact, even fiber hemp plants can re-form active agents when exposed to increased UV radiation. Take a europian fiber strain eg. to Jamaica and raise it for several generations. You will find that this 0,1% thc strain will suddenly become active again and get better and better with each generation.
I'm pretty sure this is because of the enviromental changes and mainly because of the UV radiation.
Remember, a few of the most potent strains are located to the mentioned regions where the plants gets increased UVA and B levels.
It is obvious that the plant protects itself with increased resin formation from the increased UVA/B radiation, as the latter can damage the genetic material (DNA). To trigger this self-protection, we need the "harmful" UVB radiation, IMO.
In fact, the level of a reptile tube is not as damaging to plants because it immitates conditions in deserts or jungle regions ( with 10% or 5% UVB). Even the tube manufacturers claim that the plants in the terrarium will be not damaged.

Another big LED manufacturer claims to achieve the same effect by using an extra week with only pure blue light (youtube vids).
Possible that also has a certain effect, but for really significant increases, it also needs a bit UVB in my opinion. The latest pontoons from Indagrow also have UVB-tubes(2x 54w for a 4x 4'), but use LED's for the rest of the spectrum. I think the guys from Blackdog do their claims, because it's much cheaper to just integrate UVA diodes.

 

[nfhiggs]

why run at max? nobody does that.
i put my 280mm Vesta on a aluminum profile (not a heat sink) with thermal tape and run em at about "Test current" (530mA). both rows bridged together. only 35°C on the back of the aluminum

now consider the price:
VESTA: 10.7$ for 192pcs of LEDs = 0.06$/LED
VS
F-Series: 27.1$ for 144pcs of LM561C = 0.19$/LED
3x cheaper per LED.

View attachment 4117570
EB gen2 vs Vesta spectrum
View attachment 4117548
considering efficiency:
Vesta has CRI90 and 130LM/W
Fseries & EB Gen2 have CRI80 and 180LM/W
are these Vesta strips really that much less efficient than LM561C-based strips? if 80CRI LM561C is about 180lm/W what is lm/W of 90CRI LM561C?
i wonder about PAR/watt...

Sorry, but I'm just not impressed with these at 130l/W. The Samsung strips may be 3x the cost *per diode*, but that's not really relevant when those 144 Samsung diodes are putting out nearly 3x the light (9k lumens vs 3K) at a 30% higher efficiency.

"tunability" is just not a gimmick that interests me. You can achieve the exact same thing using strips of different CCT.

 

[Randomblame]

Yupp, the Vestas are like EBgen.1 with its 83,5mA per diode but do not forget, it's CRI90!
One needs to run them at half current to get them in the gen.2 region.
When LM561c CRI80 is ~175lm/w, CRI90 would be ~145lm/w.
So from this point of view the Vestacs are not soooo shabby ...
And price it comparable to 2ft. single row F-strips.

 

[nfhiggs]

Yupp, the Vestas are like EBgen.1 with its 83,5mA per diode but do not forget, it's CRI90!
One needs to run them at half current to get them in the gen.2 region.
When LM561c CRI80 is ~175lm/w, CRI90 would be ~145lm/w.
So from this point of view the Vestacs are not soooo shabby ...
And price it comparable to 2ft. single row F-strips.

I'm just not a believer in the high CRI advantage. I think the advantages of going from 80 to 90 are marginal at best

 

[tazztone]

Samsung diodes are putting out nearly 3x the light (9k lumens vs 3K) at a 30% higher efficiency.

i think they are 3192 lm @2700K and 3352 lm @5000K.
so if you don't care about tunability you can run both rows together and it adds up to 6544lm.
6544lm/10.7$=612 Lm/$.
compared to double-row F-series: 9000lm/27.1$=332lm/$
almost double the Lumen per dollar, even if you don't care about CRI90.

now plants aren't human so don't necessarily care about Lumen.
so lets look at PPF of different CRI

active-PPF illustration with vesta spectrum superimposed:
so for PPF/WATT it's the CRI70 that wins.
but if you look at activePPF/W it's CRI90 that wins.
more specifically: 2700K and 5000K do best.
guess what: vesta has it all.[/QUOTE]

 

[nfhiggs]

i think they are 3192 lm @2700K and 3352 lm @5000K.
so if you don't care about tunability you can run both rows together and it adds up to 6544lm.
6544lm/10.7$=612 Lm/$.
compared to double-row F-series: 9000lm/27.1$=332lm/$
almost double the Lumen per dollar, even if you don't care about CRI90.

now plants aren't human so don't necessarily care about Lumen.
so lets look at PPF of different CRI
View attachment 4118926
active-PPF illustration with vesta spectrum superimposed:View attachment 4118927
so for PPF/WATT it's the CRI70 that wins.
but if you look at activePPF/W it's CRI90 that wins.
more specifically: 2700K and 5000K do best.
guess what: vesta has it all.

[/QUOTE]
That's not a proper plant activity spectrum. Try using the Mcree curve instead. Those "A-PPF/W" numbers are just a bunch of "blurple" marketing baloney. Just looking at the par numbers tells me the difference favors the higher efficiency chips.

And that price comparison ignores the significant volume discount you get with Samsung. Bridgelux offers virtually no volume discount.

They're cheaper but not nearly as efficient, not by a long shot - especially considering I can run the Samsungs balls out at 86W getting 13605 lumens (3500K) and still be 157 lm/w - a good 20% higher efficiency. To get that much light from the Vestas you'd have to push them to well over 100W - killing efficiency even more. In fact, I can get 6544 lumens from the SINGLE ROW F series strips at 41.1 watts each compared to the 48.6 watts the Vestas need.

You're much better off working with the EB Gen 2 strips. Those actually are a good alternative to the Samsungs.

Sorry but these are not the strips we're looking for.

 

[whytewidow]

These Samsung F series Gen 3 strips are awesome. I run 10 560mm strips in a 2x4x67ish. Gonna add 4 more and 3 more red strips.. running 335 watts 13.xxA 24.xxvdc just over 55k lumens. Maybe a tad more. Not couning Any reds.

 

[tazztone]

They're cheaper but not nearly as efficient

yea coz Vesta are CRI90. if Fseries were CRI 90 they would be only ~9% more efficient, as Randomblame pointed out.
so people (and plants for that matter) don't value the red shift of CRI 90? and the higher aPPF/W compared to CRI80 is completely irrelevant? i mean people are adding red/farred diodes, and CRI 90 are delivering more of these wavelengths out of the box

 

[Schalalala]

Oh jesus. Where have you been the past years? 510-610 nm drives photosynthesis very strong. Please inform yourself. This is an old myth/misunderstanding because the absoption peaks of chlorophyll where measure with isolated chlorophyll "molecules"....
I recommend this paper: https://horticulture.ahdb.org.uk/sites/default/files/u3089/Lighting_The-principles.pdf

 

[tazztone]

Oh Schalalala. i just posted the graph to show the diferent spectrums of LM561C CRI80 and Vesta CRI90.
i am not saying 510-610nm doesn't drive photosynthesis at all. but the PPF-unit values all photons from 400 to 700 nm equally. a plant does not.
anyway, PPF per WATT difference between CRI80 and 90 is only ~5%.
EB Gen2 vs VESTA:

the shift of the peak to the right is not valued by the PPF unit. also the photons above 700nm are completely discarded by the PPF unit.
YPF on the other hand actually weighs the photons at every wavelength according to a plants need.
so i am interested in the difference in YPF per Watt between CRI80 and CRI90 (or F-series and Vesta for that matter).

 

[nfhiggs]

so people (and plants for that matter) don't value the red shift of CRI 90? and the higher aPPF/W compared to CRI80 is completely irrelevant?

Yes its irrelevant when it means fewer photons overall. More light always trumps minor spectrum variance. Been proven over and over.

 

[tazztone]

Yes its irrelevant when it means fewer photons overall.

so how many photons or YPF per Watt do F-series/ VESTA have?
i think F-series probably won't justify it's price difference! you could buy 2x as much VESTAs and drive them at 50% which would further increase YPF/W.

also this study shows that the far red photons, which the CRI90 VESTA creates more of have positive effects, but they are disregarded by using PPF:
"Adding far-red (735nm) light immediately increased quantum yield of photosystem II(ΦPSII) of lettuce by an average of 6.5 and 3.6% under red/blue and warm-white light, respectively."
https://www.sciencedirect.com/science/article/pii/S0176161716302826

the spectrum shift might also contribute to the emerson effect...

 

[OneHitDone]

so how many photons or YPF per Watt do F-series/ VESTA have?
i think F-series probably won't justify it's price difference! you could buy 2x as much VESTAs and drive them at 50% which would further increase YPF/W.

also this study shows that the far red photons, which the CRI90 VESTA creates more of have positive effects, but they are disregarded by using PPF:
"Adding far-red (735nm) light immediately increased quantum yield of photosystem II(ΦPSII) of lettuce by an average of 6.5 and 3.6% under red/blue and warm-white light, respectively."
https://www.sciencedirect.com/science/article/pii/S0176161716302826

the spectrum shift might also contribute to the emerson effect...

You are clearly onto something here brother
So these VESTA's appear to be available in cob form as well?

 

[Schalalala]

A general tip: If you are interested in reading scientific papers but do not have access e.g. via university, you can use Sci-Hub to access it for free.
There a several domains, I mainly use www.sci-hub.tw but sometimes it's down then I use an alternative. Just copy the DOI from e.g. sciencedirect and paste it in Sci-Hub.
Helps a lot in doing proper research.

 

[Randomblame]

Okay, let's try from another POV!
If an F-strip single row/3000°k/CRI80 is ~175lm/w @1050mA and we use a divisor of 69* we would get ~2,536μMol/J. (24,15w per single row strip, 23v x 1050mA)

If we use ~145lm/w for Vesta 2700°k/CRI90 at half current and divide it by 62* effiency would be ~2,338μMol/J for the warmwhite channel. The coolwhite channel is a tad more efficient so we can use ~158lm/w at half current and a divisor of 65, which leads to ~2,430μMol/J.
(24w for both channels together, 2x 24v x 0,5A, Ø:2,384μMol/J)

*The divisors are taken from similar CRI90 spectrums, not calculated from Vesta SPD's, but it's close enough to show that F-strips are still better, also when CRI90 in more weighted and Vesta's running at half the nom. current.
Maybe someone has the time to calculate the correct divisors from the Vesta SPDs, but they can not be far away from the assumed values I've taken from similar spectra.

It's far away from bad or not sufficient for growing! If one prefer a tunable two channel spectra strip and want CRI90 too, why not? There are unfortunately only very few CRI90 strips and the Vesta's are one of the better ones.

 

[nfhiggs]

If we use ~145lm/w for Vesta 2700°k/CRI90 at half current and divide it by 62*

Source for those conversion numbers? The numbers I have heard are a bit different - 72 gets you within 10% at 3000k/3500/4000K and 69 gets you within 5% at 2700K. I think 65 and 62 sound a bit generous...

 

[nfhiggs]

you could buy 2x as much VESTAs and drive them at 50% which would further increase YPF/W

The Vestas are already running at half the photon output at nominal current versus the F series at 1600 mA - and still fall behind in efficiency by about 15%. Running them at 1/2 current means 1/2 the photons. You need to double the number of strips AGAIN just to keep up - now you're at 4 strips to one - for maybe another 10% efficiency. You're at almost equal efficiency for 4 times as many strips. That $40 of Vesta for $23 of Samsung (or $20 if your build is bigger - remember that volume discount?). Your efficiency hole is getting deeper my friend. Sacrificing efficiency for a bit more red just isn't worth it IMO, when you can easily add a few supplemental high efficiency red diodes to already high efficiency strips.