90 cri samsung strips

[s0me0ne]

hi guys
wanted to ask why there isnt 90 cri lm301b or lm561c chips/strips/boards?

 

[Rocket Soul]

There is, its just not available thru normal outlets. I think captain morgan had some 90cri QBs. I got some 90cri knock offs from china but god knows if theyre the real deal. Look out for bridgelux eb gen3 for next place to get 90cri strips.

 

[Moflow]

Samsung does or did have 3000K 90 cri lmc561c but in reels. Flexible strips.
I've a couple of boards with 90 Cri lmc561c on them the Growgreen boards that @VegasWinner designed and built a couple a yrs back.
I've never seen the Samsung rigid strips in 90 cri tho..... except Alibaba maybe

Bridgelux Vesta strips 90 cri

https://www.digikey.co.uk/product-detail/en/bridgelux/BXEB-TL-2750G-3000-A-13/976-1731-ND/7899252

 

[Rocket Soul]

I vouch for vestas but having gen3 ebs around the corner its prob better to wait for them.

 

[s0me0ne]

thx for the info guys

and why sellers like hlg dont build strips/boards with 90cri?are the 80 better in any way?

 

[Rocket Soul]

Lets summon @Prawn Connery again. He does a 2700k 95 cri board for flowering if youre after one.

Theres also Vesta strips from bridgelux. Or waiting for gen3.

@welight runs things at cutter.com.au and they have several offerings in 90 cri.

90 cri isnt as electrical efficient as 80 cri but it has more red in it. It seems most operations prefer to add red thru 660 diodes instead of phosphor.

 

[welight]

we have a full range of 90 cri in 2ft, Cree 2700, 3000, 3500, 4000k, 3k in V3 Nichia and 97 CRI in Nichia Optisolis in 2700, 3000, 4000 and 5000k
Cheers
Mark

 

[Prawn Connery]

thx for the info guys

and why sellers like hlg dont build strips/boards with 90cri?are the 80 better in any way?

It's a good question. CRI70 is more efficient than CRI80, which is more efficient than CRI90. But not by as much as you might think.

It all has to do with the phosphors they use on each LED and "efficacy" vs "efficiency" - which I will explain.

Most LEDs emit blue light around the 450nm range. Some of that blue light is absorbed by the phosphor (yellow or orange coloured coating on the LED) and re-emitted as red and green light. Some light energy is lost (or rather, converted to heat) when this happens. Blue light is shorter in wavelength than green and red, and has more energy (Plank's law: energy is proportional to frequency).

So the more blue light you convert to red and green, the more energy is lost. But, if you convert that same blue light to a lower frequency red (620nm vs 590nm, for example), then even more energy is lost in the conversion.

Here are some spectrum charts. Have a look at where the peaks are. Note the red peaks between 590nm and 620nm, but also look at the blue (around 450nm) and green (around 530nm) peaks:

CRI70


CRI80


CRI90


As the CRI increases, more blue light is converted to more green and red. Also, the red light is being converted into lower frequencies, from 595nm in CRI70, to 605nm in CRI80, to 615nm in CRI90. More light energy is lost at each step.

School physics taught you energy can neither be created nor destroyed, so the energy isn't actually "lost", it is just converted into other forms of energy, such as radiant heat.

OK, so "efficiency" is defined as the amount of energy that goes into a LED vs the amount of light energy (quantum radiation) that comes out.

"Efficacy" refers to how efficiently the LED converts blue light into light that is visible to the human eye, which we measure as "lumens". Lumens are weighted towards the green spectrum, which is what the human eye sees best.

So it is possible to have a LED that has higher efficiency, but lower efficacy. Which means it may be more efficient at converting energy to visible light, but it appears darker to the human eye - the more green light the LED emits, the brighter it appears for the same amount of energy.

Plants are not humans, so "efficacy" does not matter so much to them (plants have their own sensitivity to light).

Why am I taking so long to get to the point?

Because once you know why CRI80 LEDs are more efficient than CRI90 LEDS, you can understand why they might be preferable to use.

Or are they?

This is another good question.

Just like humans, plants are more responsive to certain wavelengths. You may have seen the McCree and other curves (below):


There is a whole other argument here about plant responsiveness, but to keep things simple, all you need to know is that - just like the human eye - plants use certain wavelengths more efficiently than others.

So, a CRI80 LED might be more efficient at converting blue light to red and green (which together form white light), but a CRI90 LED might be more efficient at converting that blue light into other wavelengths the plant can use - for example 620-660nm, which produces a very strong photosynthetic response in plants, especially during flowering.

To get around this, a horticultural LED manufacturer might use CRI80 LEDs as an efficient form of blue and green light, but add single-colour red LEDs (monos) to boost red output. Because the red LED produces red light which is not converted to other colours, it is also a very efficient LED.

Overall, efficiency is improved, and so is efficacy (at least in plant terms).

The real argument comes down to what is the most efficient spectrum for plants? And what is the most efficient way of meeting that spectrum?

This is were horticultural LED manufacturers may differ in opinion. There's no doubt that the "gold standard" is sunlight. But sunlight changes at different times of day, during different weather events, at different times of the year, in different parts of the world (latitudes) and even different altitudes.

And plants appear to use all of it: even green light, which is mostly reflected, plays an important part in regulating plant health and aiding photosynthesis by reflecting into the lower canopy, being absorbed deeper into the plant cells, and aiding other pigments to absorb other wavelengths, such as red.

So perhaps we could argue that the best plant spectrum is the "fullest" spectrum that is very even - just like sunlight - but weighted more towards the red part, where plants appear to photosynthesis and flower best.

That argument, I am sure, you can read and participate in elsewhere on this site.

In my opinion, there are good reasons to use high CRI LEDs, as they already produce a lot more useful light for plants (high red for example), and a fuller spectrum (more cyan, for example), even if their overall efficiency is a little bit behind CRI80. The other advantage is that high colour rendering also allows you to see the plants in their "true light", which makes picking up plant deficiencies and other problems easier.

I will touch on one other argument, and that is that CRI80 LED around 3000K has a vaguely similar spectrum to HPS light - which contains a lot of yellow, and which cannabis has been selectively bred under for the past 40+ years.

Some argue that today's cannabis responds better to more yellow light for this reason. I would argue that we have seen a better response by adding more red and a limited amount of blue (10-15%) and green. Nearly all the scientific results I have read support this. But we are constantly learning, so even the science is evolving.

 

[s0me0ne]

It's a good question. CRI70 is more efficient than CRI80, which is more efficient than CRI90. But not by as much as you might think.

It all has to do with the phosphors they use on each LED and "efficacy" vs "efficiency" - which I will explain.

Most LEDs emit blue light around the 450nm range. Some of that blue light is absorbed by the phosphor (yellow or orange coloured coating on the LED) and re-emitted as red and green light. Some light energy is lost (or rather, converted to heat) when this happens. Blue light is shorter in wavelength than green and red, and has more energy (Plank's law: energy is proportional to frequency).

So the more blue light you convert to red and green, the more energy is lost. But, if you convert that same blue light to a lower frequency red (620nm vs 590nm, for example), then even more energy is lost in the conversion.

Here are some spectrum charts. Have a look at where the peaks are. Note the red peaks between 590nm and 620nm, but also look at the blue (around 450nm) and green (around 530nm) peaks:

CRI70
View attachment 4351516

CRI80
View attachment 4351517

CRI90
View attachment 4351518

As the CRI increases, more blue light is converted to more green and red. Also, the red light is being converted into lower frequencies, from 595nm in CRI70, to 605nm in CRI80, to 615nm in CRI90. More light energy is lost at each step.

School physics taught you energy can neither be created nor destroyed, so the energy isn't actually "lost", it is just converted into other forms of energy, such as radiant heat.

OK, so "efficiency" is defined as the amount of energy that goes into a LED vs the amount of light energy (quantum radiation) that comes out.

"Efficacy" refers to how efficiently the LED converts blue light into light that is visible to the human eye, which we measure as "lumens". Lumens are weighted towards the green spectrum, which is what the human eye sees best.

So it is possible to have a LED that has higher efficiency, but lower efficacy. Which means it may be more efficient at converting energy to visible light, but it appears darker to the human eye - the more green light the LED emits, the brighter it appears for the same amount of energy.

Plants are not humans, so "efficacy" does not matter so much to them (plants have their own sensitivity to light).

Why am I taking so long to get to the point?

Because once you know why CRI80 LEDs are more efficient than CRI90 LEDS, you can understand why they might be preferable to use.

Or are they?

This is another good question.

Just like humans, plants are more responsive to certain wavelengths. You may have seen the McCree and other curves (below):
View attachment 4351519

There is a whole other argument here about plant responsiveness, but to keep things simple, all you need to know is that - just like the human eye - plants use certain wavelengths more efficiently than others.

So, a CRI80 LED might be more efficient at converting blue light to red and green (which together form white light), but a CRI90 LED might be more efficient at converting that blue light into other wavelengths the plant can use - for example 620-660nm, which produces a very strong photosynthetic response in plants, especially during flowering.

To get around this, a horticultural LED manufacturer might use CRI80 LEDs as an efficient form of blue and green light, but add single-colour red LEDs (monos) to boost red output. Because the red LED produces red light which is not converted to other colours, it is also a very efficient LED.

Overall, efficiency is improved, and so is efficacy (at least in plant terms).

The real argument comes down to what is the most efficient spectrum for plants? And what is the most efficient way of meeting that spectrum?

This is were horticultural LED manufacturers may differ in opinion. There's no doubt that the "gold standard" is sunlight. But sunlight changes at different times of day, during different weather events, at different times of the year, in different parts of the world (latitudes) and even different altitudes.

And plants appear to use all of it: even green light, which is mostly reflected, plays an important part in regulating plant health and aiding photosynthesis by reflecting into the lower canopy, being absorbed deeper into the plant cells, and aiding other pigments to absorb other wavelengths, such as red.

So perhaps we could argue that the best plant spectrum is the "fullest" spectrum that is very even - just like sunlight - but weighted more towards the red part, where plants appear to photosynthesis and flower best.

That argument, I am sure, you can read and participate in elsewhere on this site.

In my opinion, there are good reasons to use high CRI LEDs, as they already produce a lot more useful light for plants (high red for example), and a fuller spectrum (more cyan, for example), even if their overall efficiency is a little bit behind CRI80. The other advantage is that high colour rendering also allows you to see the plants in their "true light", which makes picking up plant deficiencies and other problems easier.

I will touch on one other argument, and that is that CRI80 LED around 3000K has a vaguely similar spectrum to HPS light - which contains a lot of yellow, and which cannabis has been selectively bred under for the past 40+ years.

Some argue that today's cannabis responds better to more yellow light for this reason. I would argue that we have seen a better response by adding more red and a limited amount of blue (10-15%) and green. Nearly all the scientific results I have read support this. But we are constantly learning, so even the science is evolving.

thank you for the info and your time

 

[Prawn Connery]

No worries. It's a topic that fascinates me - as you can see!

 

[DrNoob]

No worries. It's a topic that fascinates me - as you can see!

very interesting indeed, i also like bruce bugbe and his findings. but tell me prawn, what light setup do you run?

 

[ilovereggae]

It's a good question. CRI70 is more efficient than CRI80, which is more efficient than CRI90. But not by as much as you might think.

It all has to do with the phosphors they use on each LED and "efficacy" vs "efficiency" - which I will explain.

Most LEDs emit blue light around the 450nm range. Some of that blue light is absorbed by the phosphor (yellow or orange coloured coating on the LED) and re-emitted as red and green light. Some light energy is lost (or rather, converted to heat) when this happens. Blue light is shorter in wavelength than green and red, and has more energy (Plank's law: energy is proportional to frequency).

So the more blue light you convert to red and green, the more energy is lost. But, if you convert that same blue light to a lower frequency red (620nm vs 590nm, for example), then even more energy is lost in the conversion.

Here are some spectrum charts. Have a look at where the peaks are. Note the red peaks between 590nm and 620nm, but also look at the blue (around 450nm) and green (around 530nm) peaks:

CRI70
View attachment 4351516

CRI80
View attachment 4351517

CRI90
View attachment 4351518

As the CRI increases, more blue light is converted to more green and red. Also, the red light is being converted into lower frequencies, from 595nm in CRI70, to 605nm in CRI80, to 615nm in CRI90. More light energy is lost at each step.

School physics taught you energy can neither be created nor destroyed, so the energy isn't actually "lost", it is just converted into other forms of energy, such as radiant heat.

OK, so "efficiency" is defined as the amount of energy that goes into a LED vs the amount of light energy (quantum radiation) that comes out.

"Efficacy" refers to how efficiently the LED converts blue light into light that is visible to the human eye, which we measure as "lumens". Lumens are weighted towards the green spectrum, which is what the human eye sees best.

So it is possible to have a LED that has higher efficiency, but lower efficacy. Which means it may be more efficient at converting energy to visible light, but it appears darker to the human eye - the more green light the LED emits, the brighter it appears for the same amount of energy.

Plants are not humans, so "efficacy" does not matter so much to them (plants have their own sensitivity to light).

Why am I taking so long to get to the point?

Because once you know why CRI80 LEDs are more efficient than CRI90 LEDS, you can understand why they might be preferable to use.

Or are they?

This is another good question.

Just like humans, plants are more responsive to certain wavelengths. You may have seen the McCree and other curves (below):
View attachment 4351519

There is a whole other argument here about plant responsiveness, but to keep things simple, all you need to know is that - just like the human eye - plants use certain wavelengths more efficiently than others.

So, a CRI80 LED might be more efficient at converting blue light to red and green (which together form white light), but a CRI90 LED might be more efficient at converting that blue light into other wavelengths the plant can use - for example 620-660nm, which produces a very strong photosynthetic response in plants, especially during flowering.

To get around this, a horticultural LED manufacturer might use CRI80 LEDs as an efficient form of blue and green light, but add single-colour red LEDs (monos) to boost red output. Because the red LED produces red light which is not converted to other colours, it is also a very efficient LED.

Overall, efficiency is improved, and so is efficacy (at least in plant terms).

The real argument comes down to what is the most efficient spectrum for plants? And what is the most efficient way of meeting that spectrum?

This is were horticultural LED manufacturers may differ in opinion. There's no doubt that the "gold standard" is sunlight. But sunlight changes at different times of day, during different weather events, at different times of the year, in different parts of the world (latitudes) and even different altitudes.

And plants appear to use all of it: even green light, which is mostly reflected, plays an important part in regulating plant health and aiding photosynthesis by reflecting into the lower canopy, being absorbed deeper into the plant cells, and aiding other pigments to absorb other wavelengths, such as red.

So perhaps we could argue that the best plant spectrum is the "fullest" spectrum that is very even - just like sunlight - but weighted more towards the red part, where plants appear to photosynthesis and flower best.

That argument, I am sure, you can read and participate in elsewhere on this site.

In my opinion, there are good reasons to use high CRI LEDs, as they already produce a lot more useful light for plants (high red for example), and a fuller spectrum (more cyan, for example), even if their overall efficiency is a little bit behind CRI80. The other advantage is that high colour rendering also allows you to see the plants in their "true light", which makes picking up plant deficiencies and other problems easier.

I will touch on one other argument, and that is that CRI80 LED around 3000K has a vaguely similar spectrum to HPS light - which contains a lot of yellow, and which cannabis has been selectively bred under for the past 40+ years.

Some argue that today's cannabis responds better to more yellow light for this reason. I would argue that we have seen a better response by adding more red and a limited amount of blue (10-15%) and green. Nearly all the scientific results I have read support this. But we are constantly learning, so even the science is evolving.

I know its an older post but this is really great info. thank you

 

[loco41]

I know its an older post but this is really great info. thank you

I remember reading that quote a while back, thank you for bringing it up again. Seems to have sunk in a bit better this time around.

Also as a side note, arrow does have some 90cri strips available at pretty cheap prices. They use the lm561b+ diodes and have pretty low diode counts so have to be run pretty soft. There are others ones too if interested, just came across these first.

https://www.arrow.com/en/products/si-b9v111560ww/samsung-electronics

https://www.arrow.com/en/products/si-b9u111560ww/samsung-electronics

 

[ilovereggae]

I remember reading that quote a while back, thank you for bringing it up again. Seems to have sunk in a bit better this time around.

Also as a side note, arrow does have some 90cri strips available at pretty cheap prices. They use the lm561b+ diodes and have pretty low diode counts so have to be run pretty soft. There are others ones too if interested, just came across these first.

https://www.arrow.com/en/products/si-b9v111560ww/samsung-electronics

https://www.arrow.com/en/products/si-b9u111560ww/samsung-electronics

Im about to grab a bunch of Vestas and remix my QBs into full spectrum tuneable fixtures. I have 5 Vestas 2 footers now I've been using for just veg but I have some ideas I cant get out of my head and have to try it.