Latest UVA vs UVB cannabinoid test results

Grow Lights Australia

Well-Known Member
These are the latest results from our ongoing cannabinoid testing into UVA vs UVB light. The most interesting thing is the results are pretty much the same as the other tests we've done: UVA beats UVB

This might surprise some people but this is our third round of testing in two years with 13 different samples and every test we've done so far has shown a small amount of UVA and near-UV (<420nm) for 12 hours a day seems to be more effective at increasing cannabinoids (especially THC) than up to 12 hours of UVB and UVA combined.

The testing conditions were exactly the same as those in our last test here: https://rollitup.org/t/more-thc-testing-uva-vs-uvb-vs-near-uv.1010801/

This time we tested the same Afghan Skunk variety that we have used in previous tests, however we added a Cheesecake strain to the mix to see if the results would be similar and they were.

Here are the results. It is important to note that the testing facility did not know which strains were which and what had been grown under each lighting system. I will post the lighting setups and explain the samples below.


SAMPLE.........CBDA...........CBD...........CBGa...........CBG...........CBN...........d9THC...........THCa

A..........................................0.13%.............................0.80%...........................5.94%...........19.34%


A1................................................................................0.39%...........................3.47%...........15.38%


A4........................................0.15%.............................1.05%...........................6.28%...........18.58%


C1...............................................................................1.88%........0.10%.........3.32%...........23.88%


C4...............................................................................1.76%........0.98%.........3.45%...........24.12%



A.jpg

A1.jpg

A4.jpg

C1.jpg

C4.jpg
 
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Grow Lights Australia

Well-Known Member
Sample A
Afghan Skunk variety grown under a single Grow Lights Australia "High Light 420" board averaging 1000 PPFD. Coco run-to-waste, Canna nutrients. Here is the spectrum.
Speccy.jpg


Sample A1
Afghan Skunk variety grown under four Grow Lights Australia "High Red" boards with 2x Arcadia 6/30% UVB/UVA lamps running 4 hours a day (12/12 cycle) averaging 1000 PPFD. Coco run-to-waste, Canna nutrients. Here is the spectrum.

Please note that UVB does not show up in this spectograph. A spectograph of the Arcadia 6/30% UVB/UVA reptile bulb is posted below this image. Note the 550nm and 400nm peaks – they represent the proportion of light added to the High Red boards by the reptile bulbs.
Screen Shot 2019-06-16 at 21.44.13.png
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Sample A4
Afghan Skunk variety grown under four Grow Lights Australia "High Light 420" boards averaging 1000 PPFD. Coco run-to-waste, Canna nutrients. Spectrum is same as Sample A.


Sample C1
Cheesecake variety grown under four Grow Lights Australia "High Red" boards with 2x Arcadia 6/30% UVB/UVA lamps running 4 hours a day (12/12 cycle) averaging 1000 PPFD. Coco run-to-waste, Canna nutrients. Spectrum is same as Sample A1.


Sample C4
Cheesecake variety grown under four Grow Lights Australia "High Light 420" boards averaging 1000 PPFD. Coco run-to-waste, Canna nutrients. Spectrum is same as Sample A.
 

Grow Lights Australia

Well-Known Member
Explanation "A" samples
All "A" samples were the same Afghan Skunk variety.

Sample "A" was grown by @Prawn Connery and was the first test grow for the new High Light 420 boards.

Sample "A4" was grown by another grower using the same techniques (High Light 420 boards, coco run-to-waste, Canna nutrients).

The cannabinoid content of the two samples above was almost identical (26.21% vs 26.05%) which shows just how close the two growers were. This is quite remarkable considering they were grown in different places by different growers at slightly different times.

Sample "A1" was grown by the second grower (who wishes to remain anonymous) and represents the sample grown under the old High Red boards with added reptile bulbs. The cannabinoid count is quite a bit lower (19.24%) and especially hard hit were the THC and CBD levels. In fact there was no recorded CBD in the sample. Remember that this strain is exactly the same Afghan Skunk as the two other "A" samples above.


Explanation "C" samples
These were the Cheescake samples.

Sample C1 was grown by the second grower at the same time as the A1 sample under the High Red plus UVB light souces. This time the cannabinoid count was much closer.

The "C4" sample was also grown by the second grower at the same time as the "A1", "A4" and "C1" samples. It was grown under the new High Light 420 boards with no supplemental light. The 420 boards beat out the UVB sample by a small amount: 29.43% vs 29.19% total cannabinoids.

This is obviously a kick-arse strain that recorded almost 30% cannabinoid levels including 27% THC! The differences in samples are small enough to be in the margin of error, but however you look at it the UVA in the High Light 420 boards not only beat the UVB sample there was certainly no advantage to running UVB.

The last note is to point out that the reptile bulbs also have a small spectrum spike at around 365nm which is a common UVA supplement in LED lighting. However it did not seem to make much difference when compared to the 395nm+ of the High Light 420 board.

All our testing so far has shown that high UVA and near-UV from 395nm-420nm is equal to or better than UVB and UVA <395nm at increasing cannabinoid levels. What's more, high UVA and near-UV are cheaper to produce and potentially less damaging to plants and growers working underneath these lights.

These tests were conducted by an independent lab here in Australia that also conducted our last round of testing here: https://rollitup.org/t/more-thc-testing-uva-vs-uvb-vs-near-uv.1010801/
 

tstick

Well-Known Member
Good to know not to waste any money on UVB supplement. I guess I'd be most interested in finding ways to maximize terpenes and volatile esters in plants. In my experience, it makes VERY little difference in the effect I get among the plethora of complex hybrid "strains" whether they have 20% THC or 30% THC. If there are ways to increase the flavor level and intensity by using certain spectrums, then I'm all ears! But I don't think anyone is set up for that kind of testing....yet.
 

Grow Lights Australia

Well-Known Member
Controls used?
GrowOff.jpg

It was a side-by-side test. The above photo is the set-up used, however this is not the grow that was tested. For the test grow, there were six plants in the tent: an Afghan-Skunk and Cheesecake on one side, and another Afghan-Skunk and Cheesecake on the other side. Two taller sativas were grown in the middle between both lights. The plants were taller than those in this photo and effectively divided the tent in two.

Initially a blind was going to be used drawing down the centre of the tent, however it was decided to use the taller plants in the middle to block the light from each fixture, and to take each of the samples from a bud in each corner, away from the direct line of sight of the opposing light.

While this set-up is not the same as having side-by-side tents, it actually removes some of the variables such as temperature and nutrient, which were the same. I can understand if there is some scepticism regarding the division of plants, but there was enough variation in the test results to indicate each sample had its own light source.

There was also a control in the form of a separate grow of the same strain using the same High Light 420 lights, nutrients and techniques by a different grower (@Prawn Connery) which showed almost identical results for the Afhgan-Skunk variety: 26.06% (A4 sample) vs 26.21% (A sample) total cannabinoids and 22.44% (A4 sample) vs 22.77% (A sample) total THC.
 

loco41

Well-Known Member
Thanks for putting in the leg work and doing the testing for all of us.

Looked at some pictures from an old grow using just the original highlight uv boards vs this grow where I used the 6% arcadia full cycle the whole grow (I think actually started it 10ish days from sprout). Plenty of different variables between the grows, but thought it was interesting. Sadly had to chop the old grow same day of the photo and couldn't finish it but glad I at least have a couple images to compare.

First two are of the older grow with just boards and roughly 10 days ahead of this current grow at the moment. Last two are boards and uvb. Both grows same strain with similar veg time of like 5 weeks.

Sorry just thought I'd throw these out there for a little more on the subject.
 

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Grow Lights Australia

Well-Known Member
Thanks for putting in the leg work and doing the testing for all of us.

Looked at some pictures from an old grow using just the original highlight uv boards vs this grow where I used the 6% arcadia full cycle the whole grow (I think actually started it 10ish days from sprout). Plenty of different variables between the grows, but thought it was interesting. Sadly had to chop the old grow same day of the photo and couldn't finish it but glad I at least have a couple images to compare.

First two are of the older grow with just boards and roughly 10 days ahead of this current grow at the moment. Last two are boards and uvb. Both grows same strain with similar veg time of like 5 weeks.

Sorry just thought I'd throw these out there for a little more on the subject.
They look great mate!
 

MidnightSun72

Well-Known Member
First let me say thank you.
I absolutely love these posts.

This video is relevant as the researchers found it difficult to get the amount of UV correct. 1 UVB photon has 100X the energy of a UVA photon. Basically what I understood is you can use UVA UVB or UVC. But you have to adjust the dose. In the video he says they run UVB for a few hours and UVC for only seconds and still burns plants.


UVA is a lot easier on plants and humans and you can run them long/bright enough to achieve a similar effect in dose.
 

MidnightSun72

Well-Known Member
off course .... but how do you do it? ... manual or automatic .... with timers only? .... mmmm ...

I love controllers of all kinds .... curious to know that I use apogee .... or Dr Bruce to control lights ...
diming and timers? .... and in 2021? .... and I've been following Apogee since the strip .... I always liked his info and his videos ... but I don't follow fashions ... and I follow others roads .... turn the page with those of apogee, their commercial side does not add anything new to my future DIY .... I learned things from them but they stayed behind for me ....

I echoed many of their videos and their info .... and they always spent a kilo of me .... then there they .... enjoy their Olympus ... I will do it from my Paradise .. .. and all happy....

And like a certain Australian store that I will not come across again ... for ungrateful ... and high prices .... apogeee is another path that I will avoid in. my future .... ungrateful others .... with high prices ....

I prefer to move forward with others ... I will be happier ...
A simple timer is probably the easiest way. Although it could be interesting to have on a dimmer so you could increase or decrease intensity, not just with distance from canopy since we are limited to up to 12h in the case of flowering.
 

Grow Lights Australia

Well-Known Member
@salmonetin I'm not sure why your posts keep disappearing, but I did go to the trouble of translating your last post and I was going to answer it but it is not there anymore :o

What I can confirm is that when @Prawn Connery designed the first High Light boards, I know he researched those Valoya studies and used them as a basis for his design. I also know he had been speaking to local hemp famers who had told him of their own experiences with THC levels and higher UV indices such as we experience in Australia. Unlike cannabis farmers, hemp farmers need to work within a THC limit. Any environmental factors that can increase THC are detrimental because the farmers run the risk of being prosecuted for growing a drug cultivar instead of industrial hemp!

I think cannabis growers can learn a lot from industrial hemp growers.
 

Grow Lights Australia

Well-Known Member
First let me say thank you.
I absolutely love these posts.

This video is relevant as the researchers found it difficult to get the amount of UV correct. 1 UVB photon has 100X the energy of a UVA photon. Basically what I understood is you can use UVA UVB or UVC. But you have to adjust the dose. In the video he says they run UVB for a few hours and UVC for only seconds and still burns plants.


UVA is a lot easier on plants and humans and you can run them long/bright enough to achieve a similar effect in dose.
Thanks for the link. It is unfortunate that Professor Bugbee does not go into much detail in that video and seems more interested in promoting Apogee Instruments than actually explaining what UVB and UVA do to plants.

One thing that is not always taken into account is the fact that while UVB does stress the plant into producing secondary metabolites, it also destroys them. This is in addition to causing DNA damage to plants with large doses.

The most interesting thing we've noted in these experiments is that in all cases the UVB plants have higher levels of CBG and CBGa, which are the precursors to other cannabinoids. However the UVB plants also all had lower levels of overall cannabinoids including THC and CBD which leads us to believe that UVB may be effective in increasing cannabinoids, but it is also destroying them at the same time. Perhaps that is what Professor Bugbee meant when he said it was "tricky" – that there is a fine balance between stressing a plant into producing more secondary metabolites and breaking down those same secondary metabolites once produced.

The other conclusion we are starting to draw is that while UVA, near-UV and deep blue are less effective at producing cannabinoid precursors, they don't break down the final product as fast, which means more cannabinoids remain after harvest. In other words UVA and near-UV stress the plant into producing more cannabinoids than they can break down, unlike UVB which breaks down them down at a much faster rate.
 

MidnightSun72

Well-Known Member
lots disapears erased by me ... why? ... large history .... but ended on ... did the thread author like the post? ... did more people like it? ...
but it also influences that by not being able to translate it as easily as I had years ago with a better computer ... because I write a lot in Spanish ... and that makes me have to delete even more so as not to have problems in the forum and overload work to the moderators ... or the sister ... it is not easy to understand for you and the vast majority and I do not intend to bother anyone with my deletions ...

my posts or comments ... many are offtopic ... and others are on topic ... but if the author of the thread doesn't particularly like them, I end up deleting them ....
And I already warned that this year my post and comments on YT would last even less time ...
... that does not like a great majority ... but it helps me ... in my day to day ... I do not live on the opinion of others ...
., .. the deletions is a situation that will change when I have a better pc .... and I have been able to update myself on more things ...
although it gives me that by then ... I will no longer participate like now sharing ...
... I will have trouble at home ... and you get tired of talking alone or being ignored ... or not having support or brands or bros ...
I will prefer to advance with others in another way ... I am not in a hurry and I am very clear about the paths to follow ...
... that I have to go alone this time ... well, no problem at my age ... again it does not catch me ... and I have come a long way ... then no fear, fear or doubt ... what I can and what I can not do ... I will have better days or years ... and if not, they can take away the dance if they can ... lol ...

I had many bros that started in DIY and went to commercials .... many examples .... I warned many ... when you go to commercial you will lose friends .... the first one that happened was me ... and there They are in their particular Olympus ...
... for me no problem ... nothing new under the sun ... I prefer friends to money ... if they are authentic bros ... they have no price for me ... but money never was my goal .... and if theirs .... time told me the rest ....
some got to saturate them ... the SDS knows what I'm talking about ... I had many questions and a desire to learn ... they were other times ... and in my posts I played a lot and except for a few ... few They understood me ... I would say that Guod and SDs but now I am clear that I was wrong with understanding myself with SDS ... he thought other things about me ... the heavy canary nagging me again with how sad I am. ... as if I heard him speak in Greek ...

Even if they ignore me or ignore me and even hate me ... I will always love them ... we had our good times and sharing a path with them took me to another level ... and it was a pleasure on my part ... . positive mental pictures that I have on board ....


Wilson ... fictional character that I invented so as not to speak only in the posts around here ... typical also in shipwrecks in distant islands ... I know that this leads to other things ... but it is only a tool .. ... in real life I do not speak alone ... I am clear that it is real and that it is not ... it does not help me to make myself look good from the point of view of a company ... or brand to support me ... .It's very clear ... but I have to play with bad cards and do what you can with what you have .... I will have better days or years ... and better cards .... I'm not in a hurry

e function ... function eraser .... after seeing that the author of the thread did not like me and after a short time I decide whether to delete or not ... if there is a like from the author of the thread ... I usually deactivate that moderator function on board ...

fusss function ... eraser function but faster ... many times accompanied by an autobane function of those threads ...
 

MidnightSun72

Well-Known Member
@MidnightSun72

i cant look on bridgelux new software tools?.... no new tools on bridgelux yet?... mmmm ...me preocupa esa falta de info....y en estos tiempos mas.... es como si esperaran a algo para mover ficha....curioso...alguna novedad?...

e function actived.....
No they are totally unresponsive to every modern form of communication. I did not attempt to write a letter.

I did see another user was messaging Digi-Key support on the Digi-Key forums and they were also unable to get more info on the new diodes and new PCBs.

So who makes the the best UV diodes? Reliable? Is there much to care about between efficacy from UVA chip to UVA chip?
 

Grow Lights Australia

Well-Known Member
No they are totally unresponsive to every modern form of communication. I did not attempt to write a letter.

I did see another user was messaging Digi-Key support on the Digi-Key forums and they were also unable to get more info on the new diodes and new PCBs.

So who makes the the best UV diodes? Reliable? Is there much to care about between efficacy from UVA chip to UVA chip?
We've done a bit of UV testing. In fact, LED Teknik has done a lot of real-world testing of UV diodes and the tested efficiencies have ranged from 40% up to more than 70%. Efficiency has almost as much to do with the wavelength as it does the manufacturer. For example wavelengths around 395-405nm tend to be most efficient and then drop off as you get to higher wavelengths until you hit about 450nm. They also drop off below 395nm.

The most efficient UV diodes LED Teknik has tested are the new Nichia 405s (3535 format) which came in at around 71-72%. We looked at including these on our High Light 420 boards, but to include one high-power UV diode we'd need to remove one of the 660s. We'd also need to include a Seoul Semiconductor or another type of purple pump white phosphor mid-popwer (3030) LED to get the 405-430nm range up. After we did all that, board efficiency was still about the same as it is now, but with less red and a heavier UV rating. We may still produce a few boards in this configuration for those who want extra UV, but what we're learning is that when it comes to UV, a little goes a long way so you don't need that much.
 
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