New lights, new spectra and some High Light strips

[Prawn Connery]

Yes, d8thc, an isomer? made from hemp(cbd isolate)

Industrial hemp products can't be sold for human consumption here. Some companies are selling CBD extracts as pet medications – and some sell it to humans on the black market – but I haven't heard anything about D8THC here. Admittedly I'm not that involved anymore, but I have a friend who straddles both sides of the fence (CBD for human consumption) so I will ask him next time I see him if there is any interest. Sorry, that's all I know.

 

[PSUAGRO.]

Industrial hemp products can't be sold for human consumption here. Some companies are selling CBD extracts as pet medications – and some sell it to humans on the black market – but I haven't heard anything about D8THC here. Admittedly I'm not that involved anymore, but I have a friend who straddles both sides of the fence (CBD for human consumption) so I will ask him next time I see him if there is any interest. Sorry, that's all I know.

No worries, was just wondering ... ... Forgot how draconian the laws are in oz.

 

[Scuzzman]

No worries, was just wondering ... ... Forgot how draconian the laws are in oz.

you should try NZ the laws are stupid

 

[Sparkled]

I can answer this. Narrow band phosphors are more efficient and on their own they are nice diodes. But they cost a little more and they suffer the same as CRI80 diodes that have very little cyan and not a lot of deep or far red that you will find in a typical CRI90 phosphor. That is why they are called "narrow band" because they have a narrow band of red that bumps the CRI with no efficiency penalty but in all other respects have a similar spectrum profile to a typical CRI80 diode.

Narrow band phosphors (CRI90)
vs
Typical phosphor (CRI90)

- Which is better for FLOWER stage ?

 

[Grow Lights Australia]

Narrow band phosphors (CRI90)
vs
Typical phosphor (CRI90)

- Which is better for FLOWER stage ?

Broad-band phosphor. This graph is from Lumileds: https://www.lumileds.cn.com/wp-content/uploads/files/WP32.pdf



What indoor lighting manufacturers call "wasted light" is exactly what plants thrive under. The broad phosphor has more and deeper red, as well as far red and slightly less green. There is a little bit more area under the curve for the broad-band LED which means their peaks (blue line) are a little bit lower in reality compared to the narrow-band (red line) peaks.

We use narrow bands to boost red in the 610-630nm region to target Chlorophyl B and we already have 660nm and 730nm diodes to boost the deep red and far red regions, but if we used only one type of LED it would be CRI90 broad-band because of the more balanced red spectrum including far red which has shown proven results.

The narrow-band phosphor in theory should be slightly more efficient and it will have a higher lm/w efficiency but not necessarily higher umol/j. The 3000K narrow band phosphors we use are 2.77 umol/j while the CRI90 2700K Nichia broad-band phosphors we use are 2.75 umol/j. Hardly any difference in photometric efficiency but a lot more red and far red in the 2700K diodes which are better for flowering.

 

[Rocket Soul]

Narrow band phosphors (CRI90)
vs
Typical phosphor (CRI90)

- Which is better for FLOWER stage ?

This question makes more sense if you take into account what else is added to the spectrum: narrow band seems to lack a bit in far red output in comparison to broadband 90 cri but if you this you can make up for by adding far red diodes, like in the gla boards.
You could arguably make a case for broadband having a fuller spectrum since it adds more far red to the mix. But even so weve had crops where 90cri did better, and some standard 3000k 80cri did better with all same conditions, theres some strain dependence in there also

 

[Speedtriplebbc]

So it seems to me… with 630nm diodes not being very efficient alongside wide band phosphorus white diodes, adding a narrow band will give a spike that’s beneficial for plant growth in a similar way to a mono led. Although I’m the same way a mono needs to be mixed with whites, these will still need to be blended in with whites. I think someone will correct me if I’m wrong as this is just what I’ve worked out myself. I suspect this is why many boards don’t contain 2700k cri90? The ones that you find like the original highlights and my trusted highlight uv boards actually seem quite poor in efficiency compared with many new boards like the highlight 420’s. Although they’re still a better performer than HPS in my opinion.
I pretty much gave up chasing 630nm, I love to have a broad spectrum but 660nm is so efficient and the plants don’t seem to be bothered. Every now and then I look at my spare 4000k cri80 Samsung strips and consider how to make them into a great full spectrum grow light so that’s the only reason I came across the Bridgelux diodes. The strips only became redundant when I saw the gen1 highlights and they took away all the calculations and wiring it would have took.

 

[Prawn Connery]

So it seems to me… with 630nm diodes not being very efficient alongside wide band phosphorus white diodes, adding a narrow band will give a spike that’s beneficial for plant growth in a similar way to a mono led. Although I’m the same way a mono needs to be mixed with whites, these will still need to be blended in with whites. I think someone will correct me if I’m wrong as this is just what I’ve worked out myself. I suspect this is why many boards don’t contain 2700k cri90? The ones that you find like the original highlights and my trusted highlight uv boards actually seem quite poor in efficiency compared with many new boards like the highlight 420’s. Although they’re still a better performer than HPS in my opinion.
I pretty much gave up chasing 630nm, I love to have a broad spectrum but 660nm is so efficient and the plants don’t seem to be bothered. Every now and then I look at my spare 4000k cri80 Samsung strips and consider how to make them into a great full spectrum grow light so that’s the only reason I came across the Bridgelux diodes. The strips only became redundant when I saw the gen1 highlights and they took away all the calculations and wiring it would have took.

The original High Light boards were 2.5 umol/j which was surprisingly high for their time and also considering they were CRI94-95. The Optisolis and Seoul Semiconductor UV Sunlike LEDs were not that efficient (around 2.1-2.2 umol/j), but the 2700K CRI90 Nichias are still up there (2.75 umol/j) which dragged the efficiency up – which is why I used them.

We managed to get 20% better efficiency from the High Light Light 420 boards, but that was only after doing a lot of individual LED testing with LED Teknik and mainly because we had access to some 3.94 umol/j 660 monos. We now have access to a new batch of 660s that are testing 4.1-4.2 umol/j, so the Gen 3 (or whatever it is we come up with next) will be even more efficient.

Overall, however, it is really hard to get that kind of efficiency from ANY LED that contains UV and Far Red. The 405nm Nichias we use now are 71-72% efficient but still only around 2.3 umol/j because they have a very low QER of 3.36 (the theoretical maximum umol/j for a spectrum if the diode is 100% efficient).

720nm Far Red diodes, on the other hand, are still only around 55% efficient – even, though they have a high QER of 5.99

 

[Speedtriplebbc]

The original High Light boards were 2.5 umol/j which was surprisingly high for their time and also considering they were CRI94-95. The Optisolis and Seoul Semiconductor UV Sunlike LEDs were not that efficient (around 2.1-2.2 umol/j), but the 2700K CRI90 Nichias are still up there (2.75 umol/j) which dragged the efficiency up – which is why I used them.

We managed to get 20% better efficiency from the High Light Light 420 boards, but that was only after doing a lot of individual LED testing with LED Teknik and mainly because we had access to some 3.94 umol/j 660 monos. We now have access to a new batch of 660s that are testing 4.1-4.2 umol/j, so the Gen 3 (or whatever it is we come up with next) will be even more efficient.

Overall, however, it is really hard to get that kind of efficiency from ANY LED that contains UV and Far Red. The 405nm Nichias we use now are 71-72% efficient but still only around 2.3 umol/j because they have a very low QER of 3.36 (the theoretical maximum umol/j for a spectrum if the diode is 100% efficient).

720nm Far Red diodes, on the other hand, are still only around 55% efficient – even, though they have a high QER of 5.99

I am certainly thankful for those highlight uv boards that I still use and not in a hurry to replace. I was chasing spectrum more than efficiently at first, although as you say it’s great for it’s time without any mono’s in there too. Pretty sure if I wait for some pc blue buddies and throw in my 660/730 buddies they’ll be brought up to date a little.

 

[Dr.Strain]

How about them new Gavita pro 1700e LED lights with the samsung diodes though

 

[Speedtriplebbc]

How about them new Gavita pro 1700e LED lights with the samsung diodes though

Compared to the more impressive old highlight uv boards that I we just discussed or the newest highlight 420 gen2 with a broader spectrum and higher efficiency? Because personally I’d still use the original highlight uv over that. I’m not slating Gavita, it’s personal choice but it’s off topic and I personally wouldn’t be happy with that without paying for a load of extra strips and diodes to be able to stretch the spectrum into the violets and far reds for improving quality overall. If I was a commercial grower after quantity over quality then I’d still hesitate because I’d want to keep it nearer 3umol/j for efficiency. I’m sure there’s plenty of people who would be happy with the improvement over HPS but I wouldn’t replace a Philips 315w CMH 3100k with the Gavita, possibly chequerboard them though?

 

[Kassiopeija]

Overall, however, it is really hard to get that kind of efficiency from ANY LED that contains UV and Far Red. The 405nm Nichias we use now are 71-72% efficient but still only around 2.3 umol/j because they have a very low QER of 3.36 (the theoretical maximum umol/j for a spectrum if the diode is 100% efficient).

720nm Far Red diodes, on the other hand, are still only around 55% efficient – even, though they have a high QER of 5.99

Aha very interesting, I believe Bugbee established in recent times that these far-red photons count similar towards photosynthesis as normal PAR light.
Physically a 720nm photon holds less energy than a 660nm one which - in theory - could imply that farred diodes could deliver more umols/J than the blue-shifted brothers. Perhaps making farred boards most efficient in the future?

 

[Speedtriplebbc]

Aha very interesting, I believe Bugbee established in recent times that these far-red photons count similar towards photosynthesis as normal PAR light.
Physically a 720nm photon holds less energy than a 660nm which - in theory - could imply that farred diodes deliver more umols/J than the blue-shifted brothers. Making farred boards most efficient in the future?

To be fair, PAR as I believe is based on old data for general plant growth not specifically cannabis, otherwise we’d see great results off blurples. I admit some of this technical information is a little over my head although I understand the general idea with peoples explanations here. I’ll be looking into this later as it sounds like it could be right?

 

[coreywebster]

Something to look forward too!!!!
I'm excited

 

[Prawn Connery]

How about them new Gavita pro 1700e LED lights with the samsung diodes though

How about them? They're just like all the other Chinese bar lights. Same spectrum, same format.

Two of these will destroy a Gavita for less money – 740W power draw, "true" full spectrum (390nm-780nm), height adjustable at different levels, remotely mounted Mean Well drivers with 7-year warranty, made in Australia with Nichia (better than Samsung) and LED Teknik (better than Osram) diodes, and proven in grow rooms around the world.

 

[Prawn Connery]

Aha very interesting, I believe Bugbee established in recent times that these far-red photons count similar towards photosynthesis as normal PAR light.
Physically a 720nm photon holds less energy than a 660nm one which - in theory - could imply that farred diodes could deliver more umols/J than the blue-shifted brothers. Perhaps making farred boards most efficient in the future?

720nm has a higher QER (5.99 calculated) but the efficiency is still low compared to 660nm.

It's interested the way Far Red works as it is intuitive to think that it doesn't drive photosynthesis because the electron chain in PS2 ends at 680nm before passing its electron to PS1 which ends at 700nm. You would think that with energy losses you could not go the other way: an electron chain starting with 720nm can't gain energy back to 700 or 680, so in theory can't drive a light engine.

I think I read somewhere tha Far Red has a quenching effect that makes photosynthesis more efficient when combined with red below 700nm.

 

[Speedtriplebbc]

720nm has a higher QER (5.99 calculated) but the efficiency is still low compared to 660nm.

It's interested the way Far Red works as it is intuitive to think that it doesn't drive photosynthesis because the electron chain in PS2 ends at 680nm before passing its electron to PS1 which ends at 700nm. You would think that with energy losses you could not go the other way: an electron chain starting with 720nm can't gain energy back to 700 or 680, so in theory can't drive a light engine.

I think I read somewhere tha Far Red has a quenching effect that makes photosynthesis more efficient when combined with red below 700nm.

This is exactly what I was saying about only just following what’s going on, lol. Am I correct in saying that far red is outside of PAR and that’s why it often reduces efficiency figures? If so I can see why many companies don’t add far red as despite helping, it would probably reduce the efficiency and not look as good on paper as some competitors without far red?
Also, would the quenching effect you mentioned be part of the Emerson effect?

 

[Kassiopeija]

It's interested the way Far Red works as it is intuitive to think that it doesn't drive photosynthesis because the electron chain in PS2 ends at 680nm before passing its electron to PS1 which ends at 700nm. You would think that with energy losses you could not go the other way: an electron chain starting with 720nm can't gain energy back to 700 or 680, so in theory can't drive a light engine.

Oh yes Far-Red can definitely drive photosynthesis and that has been proven by so many studies who investigated into the exact mechanisms the proof is out there 100-fold.
Far-red drives an "uphill" photosynthesis where a far-red photon gets absorbed by these 'red-chlorophylls' and the missing energy is added from the heat prevalent in this system.

I think I read somewhere tha Far Red has a quenching effect that makes photosynthesis more efficient when combined with red below 700nm.

with any light more blue-shifted than 680nm, although there exist a few select wavelengths in PAR where PS1 & PS2 absorb almost equally. But that is within a very narrow range.
Far-Red enables it that the white light captured by PS2 can be used swifter. Plus its integration of phononic energy into this process has a cooling photoprotective effect on the PS1 core. Some of the (fary)'red chlorophylls' that sit very close to the PS1 reaction center also have a very beneficial trapping kinetic.

It's kind of sad that many studies regarding photosynthetic efficiency of the various colors didnt include FR in their recipe - I suspect that alot of positive results from overtly red 660nm recipes stem from the touching into the E.E. PS1 excitation. Esp. considering many of these experiments have been driven at mediocre irradiance.

 

[Grow Lights Australia]

This is exactly what I was saying about only just following what’s going on, lol. Am I correct in saying that far red is outside of PAR and that’s why it often reduces efficiency figures? If so I can see why many companies don’t add far red as despite helping, it would probably reduce the efficiency and not look as good on paper as some competitors without far red?
Also, would the quenching effect you mentioned be part of the Emerson effect?

Hi Speedtriplebbc you are right. Traditional PAR is defined as 400-700nm so anything outside those wavelengths is not counted in most PPFD readings. More than 10% of the light in our boards falls outside 400-700nm so a PPFD reading of 900 for one of our boards is close to 1000 in reality. As PC has explained far red diodes are not very efficient so even though they need less energy to create a photon of light they are not that efficient to begin with. To calculate umol/j you multiply efficiency by Quantum Efficiency of Radiation (QER). QER is a measure of how many photons you can make with 1 joule of energy based on the spectrum. Shorter wavelengths like blue and UV require more energy to make a photon so have a lower QER. Longer wavelengths like deep red and far red require less energy. Some LEDs have high efficiency but low QER like Nichia's 405nm UV which is almost 72% efficient but has a QER of around 3.3 and other diodes like typical 720-730nm monos have low efficiency but high QER. Many 660 monos have high efficiency and a high QER so they convert the most energy into light and have the highest umol/j readings. I'm sorry I'm not sure what Prawn was talking about regards the Emerson Effect. I'm sure he will explain.

 

[Grow Lights Australia]

How about them new Gavita pro 1700e LED lights with the samsung diodes though

Hi Dr.Strain I don't want to criticise another manufacturer's lights but can you tell us what you think is so special about the Gavita or are you asking us? I'm not sure if that was a question! They just appear to be normal bar lights with Samsung and Osram diodes. Lots of manufacturers make them. I know Gavita had a good name in HIDs but a lot of HID manufacturers were late to develop LEDs and now most of them seem to copy each other and nearly all of them are made in China. There are some innovative lesser-known companies out there like Valoya and of course us (I had to say that!). There are other companies that I know that also have good spectrums but are perhaps not as efficient. Efficiency is good but efficiency with spectrum is better. I note that the Gavita is 2.6 umol/j efficient but once you start adding separate bars of UV and far red diodes the cost goes up and the efficiency goes down. I don't think a lot of people realise just how efficient our lights are when you consider the amount of far red and UV in them.