It's always right that you want the stats of a growlight given not in lumens but in photon flux (flux density) Although the bad rep of green light is getting better: Just to give a little bit of extra info: the cree action curve is looking to be disbanded/replaced by newer science. It was measured using monochromatic light meaning each frequency (wavelength) was measured distinctly while everything else was filtered out. The main outcome was that there was very low photosynthetic efficiency in the yellow/green spectrum and only blue and red really counted towards photosynthesis. Newer measurments with multicolored (white) light show that green/yellow have quite hight efficiency also when used with blue and red present at the same time. So there seems to be quite a notable 'entourage' effect in photosynthesis. It seems the effects have not yet been concluded to a new action spectrum. It may still be true that light with more red/blue and less yellow/green are better - but the effect is not nearly as strong as the old cree action spectrum suggests. Also it is showing that wavelength outside the cree spectrum (uv and far red) also add to plant growth, with uv driving essential plant oils up (useful in cannabis) and far red driving leave size (useful in lettuce). Pretty much everyone is now going for massive white light and additional 660nm reds (phosphor is sharply dropping radiation above 620nm). I can see that it may be viable to have like 10% blue and red to switch between veg and flowering. Look up Bruce Bugbee ( Utah State University/ apogee sensors) for that.
Feedback: I'd say as a DIY, I wouldn't build a white only LED. A huge factor is availability, I don't think you will find 95+CRI out there in the wild too often. I just designed a white blend of 2.7/3K and 5K with 660/740/420(!) enhancements. Before I watched, I designed mine as a 6:1 Red/Blue, and all fully dimmable, so I am glad to see my analysis is agreed upon by another Electronic Savvy Horticulturist.
Excellent Marra, concise, succinct and to the point. I didn't understand everything that you talked about, but that's a good thing as I realised I need to learn more; meaning I'll be back. Easy'!
Very well explained. Thank you! Although the most recent studies revaluate the immense importance of green radiation for plants growth and dismiss the old mith of blue and red. being the only radiations useful to plants...
Very interesting video, I have found the 4500k lights to be the closest to mid day sun and have very acceptable lumens so I use those in my aquariums, easier on the fish's eyes than too much uv or super whites. One thing I have found uv particularly good for is growing types of algae, particularly green spot algae and green dust algae, I found the high red spectrum combined with uv's . The green dust algae may be a type of cyanobacteria but I can't confirm. A multiband diy light I made with a Chinese multidiode configuration grew a whack ton of yellow cyanobacteria in one of my tanks when I was high fertilizing with an organic sea kelp extract. Obviously some of the cyanobacteria in there wasn't dead yet 😬💉. And I've tried using all red lighting and got significantly more green dust algae than when using regular white spectrums. I think it has something to do with the color wheel reaction in the chloroplasts. I have heard that chloroplasts like to reflect blue light rather than capture it which could explain why metal halides generally were not as good as high pressure sodiums for plant specs.
What’s up Rich great videos man you’re very awesome dude keep up the good work you break down everything so well PS any recommendation for lights out already built or how can I build to work can I get the accessories can you show us in a video I would love to see it for people who are amateurs and Pros that need a little extra help thank you so much
Well I do know some methods to lower the lumens to 0, of which selling the light is the most efficient. Ok joking aside: Unless the driver of the tube already has a dimming function onboard it's probably not worth to invest in a led dimmer: too expansive. To alter the color temp is also not advisable. You could lower it by using some kind of foliage or glass filtering out some of the blue photons which would also reduce the efficiency. Just buy a better suited light would always come cheaper I think.
Thank you, sir! This is a very inspiring video, especially regarding the luminance of light. So, footcandles, lux, and lumens - each of these measurement units are based solely on a human's eye perception model and cannot be used to quantify the power of light, right? Also, in terms of growing efficiency, it's very interesting which LED setup shows the best results. Meaning, is it still a good-old combination of "red, red, deep blue and full spectrum white" (like in Plant Photonics "Amethyst" series), or is the full full-spectrum white setup (like in "Stellar" series) already wins the race??
Sorry for the delay in replying (I didnt see your comment) and thanks for the order! Yes correct, footcandles, lux, and lumens are only relevant to human eyes, not plants. For maximum efficiency red/blue/white gives the most growth for the watts consumed. The main advantage of white is its more pleasant on the eye and makes it easier to spot problems with the plants, but you will need about 20% more watts than with r/b/w.
It's always right that you want the stats of a growlight given not in lumens but in photon flux (flux density)
Although the bad rep of green light is getting better:
Just to give a little bit of extra info: the cree action curve is looking to be disbanded/replaced by newer science.
It was measured using monochromatic light meaning each frequency (wavelength) was measured distinctly while everything else was filtered out. The main outcome was that there was very low photosynthetic efficiency in the yellow/green spectrum and only blue and red really counted towards photosynthesis.
Newer measurments with multicolored (white) light show that green/yellow have quite hight efficiency also when used with blue and red present at the same time. So there seems to be quite a notable 'entourage' effect in photosynthesis.
It seems the effects have not yet been concluded to a new action spectrum. It may still be true that light with more red/blue and less yellow/green are better - but the effect is not nearly as strong as the old cree action spectrum suggests.
Also it is showing that wavelength outside the cree spectrum (uv and far red) also add to plant growth, with uv driving essential plant oils up (useful in cannabis) and far red driving leave size (useful in lettuce).
Pretty much everyone is now going for massive white light and additional 660nm reds (phosphor is sharply dropping radiation above 620nm). I can see that it may be viable to have like 10% blue and red to switch between veg and flowering.
Look up Bruce Bugbee ( Utah State University/ apogee sensors) for that.
Feedback: I'd say as a DIY, I wouldn't build a white only LED. A huge factor is availability, I don't think you will find 95+CRI out there in the wild too often. I just designed a white blend of 2.7/3K and 5K with 660/740/420(!) enhancements. Before I watched, I designed mine as a 6:1 Red/Blue, and all fully dimmable, so I am glad to see my analysis is agreed upon by another Electronic Savvy Horticulturist.
Your videos are excellent. Proper Science. Not the usual 'street science'. Brilliant........
thanks a lot, it's the best explanation that I've come across
Excellent Marra, concise, succinct and to the point. I didn't understand everything that you talked about, but that's a good thing as I realised I need to learn more; meaning I'll be back.
Easy'!
Thank you for the lesson I really appreciate the explication.
Interesting. Where were the charts from 11:17 to 14:02 taken from?
I learned a ton my friend and thank you!
Very well explained. Thank you!
Although the most recent studies revaluate the immense importance of green radiation for plants growth and dismiss the old mith of blue and red. being the only radiations useful to plants...
I dont understand if u could tell me wat size power supply i need AC100-24V input is 100-240~2A 50/60Hz output is 24VDC 3.5A
Very interesting video, I have found the 4500k lights to be the closest to mid day sun and have very acceptable lumens so I use those in my aquariums, easier on the fish's eyes than too much uv or super whites.
One thing I have found uv particularly good for is growing types of algae, particularly green spot algae and green dust algae, I found the high red spectrum combined with uv's .
The green dust algae may be a type of cyanobacteria but I can't confirm.
A multiband diy light I made with a Chinese multidiode configuration grew a whack ton of yellow cyanobacteria in one of my tanks when I was high fertilizing with an organic sea kelp extract. Obviously some of the cyanobacteria in there wasn't dead yet 😬💉.
And I've tried using all red lighting and got significantly more green dust algae than when using regular white spectrums.
I think it has something to do with the color wheel reaction in the chloroplasts.
I have heard that chloroplasts like to reflect blue light rather than capture it which could explain why metal halides generally were not as good as high pressure sodiums for plant specs.
What’s up Rich great videos man you’re very awesome dude keep up the good work you break down everything so well PS any recommendation for lights out already built or how can I build to work can I get the accessories can you show us in a video I would love to see it for people who are amateurs and Pros that need a little extra help thank you so much
So in the graphs you show warm white (in yellow colour) and white (in blue colour). Is that the difference in Kelvin?
warm is generally 2.7K to 3.5K Neutral is 4K-5K, Cool is 5.7K+
@@LRandleIcon Thanks! So I guess the blue line was neutral?
Thanks!
ah that was pretty awesome ....still confused but in a better way
could someone defuse a led 6000 K 1900 lumens T8 tube light, to lower the Kelvin and or lumens???
Well I do know some methods to lower the lumens to 0, of which selling the light is the most efficient.
Ok joking aside:
Unless the driver of the tube already has a dimming function onboard it's probably not worth to invest in a led dimmer: too expansive. To alter the color temp is also not advisable. You could lower it by using some kind of foliage or glass filtering out some of the blue photons which would also reduce the efficiency. Just buy a better suited light would always come cheaper I think.
Thank you, sir! This is a very inspiring video, especially regarding the luminance of light.
So, footcandles, lux, and lumens - each of these measurement units are based solely on a human's eye perception model and cannot be used to quantify the power of light, right?
Also, in terms of growing efficiency, it's very interesting which LED setup shows the best results.
Meaning, is it still a good-old combination of "red, red, deep blue and full spectrum white" (like in Plant Photonics "Amethyst" series), or is the full full-spectrum white setup (like in "Stellar" series) already wins the race??
Sorry for the delay in replying (I didnt see your comment) and thanks for the order! Yes correct, footcandles, lux, and lumens are only relevant to human eyes, not plants. For maximum efficiency red/blue/white gives the most growth for the watts consumed. The main advantage of white is its more pleasant on the eye and makes it easier to spot problems with the plants, but you will need about 20% more watts than with r/b/w.
Learned a lot. Thank you. Where is your accent from? It sounds American.....but not?
Thanks!