Full spectrum led?

[Rahz]

its called Perfect Sun Black Diamond Line

Well, maybe. Website states Cree XT-E but also mentions Bridgelux 5w.

What emitters are used? How many of each? What current? Only then can a person take the initiative to look up the datasheets, crunch some numbers and figure out a reasonable PPF estimate.

One example from their website- "It has 1200 par at 24 inches away."

a spot PPFD reading isn't enough information to determine PPF.

So maybe it's a good light, but how do you know?

 

[Rahz]

For that matter, a really crappy blurple light would work fine for testing spectrum -vs- spectrum. Stick a good par meter in there. Dial it in so the readings are the same as a white test area. Grow and examine results.

That would provide information on whether blurple is worth pursuing. Then we would have to deal with efficiency. Blurple could be the perfect spectrum but if a lamp manufacturer doesn't provide good output numbers and part numbers for checking their math, they're making it very difficult to justify the purchase for those who like to know what they're getting.

If the best a blurple can do is 50% efficiency and someone else can build a 60% efficient white lamp for the same price, the blurple spectrum would need to be about 20% more effective to justify the purchase.

 

[InTheValley]

Well, maybe. Website states Cree XT-E but also mentions Bridgelux 5w.

What emitters are used? How many of each? What current? Only then can a person take the initiative to look up the datasheets, crunch some numbers and figure out a reasonable PPF estimate.

One example from their website- "It has 1200 par at 24 inches away."

a spot PPFD reading isn't enough information to determine PPF.

So maybe it's a good light, but how do you know?

i have 1, thats how. I have the Mini version, and its a pretty dam good light, just not big enough for my 3x3, hits 1000PAR at 16 inches under the center,

 

[Rahz]

A lot of people would like to see you run that side by side, either equal par map or wattage -vs- white and post final yield numbers. I've been hoping someone would do it for years. People with crappy blurple lamps generally don't have nice par meters.

 

[Yodaweed]

That is not remotely true?
My light contains both, and wasn't that expensive.

Nope your LED does not contain UV or IR light. Sorry to burst your bubble but grow light LEDs don't contain those in the spectrum you need to supplement them.

Tell me what kind of LED i'd be happy to pull up a chart and show you your lights spectrum since you do not know.

 

[Yodaweed]

For that matter, a really crappy blurple light would work fine for testing spectrum -vs- spectrum. Stick a good par meter in there. Dial it in so the readings are the same as a white test area. Grow and examine results.

That would provide information on whether blurple is worth pursuing. Then we would have to deal with efficiency. Blurple could be the perfect spectrum but if a lamp manufacturer doesn't provide good output numbers and part numbers for checking their math, they're making it very difficult to justify the purchase for those who like to know what they're getting.

If the best a blurple can do is 50% efficiency and someone else can build a 60% efficient white lamp for the same price, the blurple spectrum would need to be about 20% more effective to justify the purchase.

Blurple lights are like click bait, real high par numbers but that doesn't matter because their spectrum is terrible. Too much blue which bloats par numbers and does not do well for flowering plants.

PAR can be a good measurement, it can also be a crap one, blue LEDs have much higher PAR than any other type of LED, it's why blurple lights output is high as hell in a par chart but they suck shit in a grow room.

 

[Rahz]

Blurple lights are like click bait, real high par numbers but that doesn't matter because their spectrum is terrible. Too much blue which bloats par numbers and does not do well for flowering plants.

It varies. Flip Chip for instance allows you to choose what percentage of blue and red you want in your cobs. If they were even close to Samsung, Vero29C, Citizen etc. in terms of efficiency they would be worth taking a look at.

@Randomblame does make a very good point though. It prompted me to dig up some old data and look at it again. I've arranged it into a summary chart.



Rows 3-5 - spectral analysis
Row 7 - Raw PPFD readings
Row 8 - Raw readings with Mcree correction factor.
Rows 10, 13, 16 - Relative intensity: % * raw reading / 100
Rows 11, 14, 17 - (10, 13, 16) with Mcree correction factor.


It would have been nice if 4000K 80CRI had been included in the mix, but we can predict with some degree of accuracy the values based on the available data. This wouldn't be true of 5000+ because the spectral curves become very different. If we extrapolate 4000K 80CRI from the data the Blue/Green/Red %s would be around 16.5/46/37.5. PPFD reading would be about 936 and with Mcree correction it wouldn't be much different than 3000K 80CRI or 3500K 80CRI.

CRI- 80CRI provides about 10% red (600-700nm) boost over 70CRI. 90CRI provides about 10% red boost over 80CRI. CRI has a minor impact on blue output. This is all at the expense of the 500-600nm regions. 3000K 70CRI Has the highest par readings by far. Even when a correction factor based on the Mcree curve is applied 3000K 70 CRI still has the highest score due to all the light in the 500-600 region. The sample with the highest R + B is 3000K 90CRI.

K- Blue levels drop about 40% going from 3000K to 2700K. Blue levels increase by about 15% from 3000 to 3500K. 2700K has a slight increase over 3000K in red. 3000K 80CRI has around 8% more red than 3500K 80CRI.

From the samples I think 3000K 70CRI would be a good dedicated veg spectrum, also 4000K 70 or 80CRI. Any of them will get the job done but it wouldn't be intuitive to use 2700K 90CRI for instance, but it might make sense to use 3000K 70CRI full cycle. Regarding flowering and yield, I have no idea which is best. On paper 3000K 70CRI should provide the best yield (YPF) once the phosphor losses are factored in. In practice nobody seems to have shown one to be better grow after grow, Just different and conflicting reports.

20 par watts per foot from most any light source is going to do a really good/similar job. I prefer 3000K 90CRI but more because it seems like the ideal spectrum, rather than because of some guarantee it will work better. I don't care to have UV in my grow space and don't see the point in anything beyond 700nm except perhaps for lights out. If a lamp came with end of day functionality that would be a nice selling point. DIY there are various options for that and UV bulbs if UV is desired.

Why one of the cool kids hasn't built a blurple lamp and qualified it against white after all these years of people DIYing, I don't know. I guess there's a practicality to the design and build process that precludes building things one might not want to use after it's built, or would cost more than necessary to do the same job. Still, it's entirely possible to DIY a high efficiency 450+630+660 lamp and quantify the output to a high degree of accuracy.

 

[Yodaweed]

It varies. Flip Chip for instance allows you to choose what percentage of blue and red you want in your cobs. If they were even close to Samsung, Vero29C, Citizen etc. in terms of efficiency they would be worth taking a look at.

@Randomblame does make a very good point though. It prompted me to dig up some old data and look at it again. I've arranged it into a summary chart.

View attachment 4227308

Rows 3-5 - spectral analysis
Row 7 - Raw PPFD readings
Row 8 - Raw readings with Mcree correction factor.
Rows 10, 13, 16 - Relative intensity: % * raw reading / 100
Rows 11, 14, 17 - (10, 13, 16) with Mcree correction factor.


It would have been nice if 4000K 80CRI had been included in the mix, but we can predict with some degree of accuracy the values based on the available data. This wouldn't be true of 5000+ because the spectral curves become very different. If we extrapolate 4000K 80CRI from the data the Blue/Green/Red %s would be around 16.5/46/37.5. PPFD reading would be about 936 and with Mcree correction it wouldn't be much different than 3000K 80CRI or 3500K 80CRI.

CRI- 80CRI provides about 10% red (600-700nm) boost over 70CRI. 90CRI provides about 10% red boost over 80CRI. CRI has a minor impact on blue output. This is all at the expense of the 500-600nm regions. 3000K 70CRI Has the highest par readings by far. Even when a correction factor based on the Mcree curve is applied 3000K 70 CRI still has the highest score due to all the light in the 500-600 region. The sample with the highest R + B is 3000K 90CRI.

K- Blue levels drop about 40% going from 3000K to 2700K. Blue levels increase by about 15% from 3000 to 3500K. 2700K has a slight increase over 3000K in red. 3000K 80CRI has around 8% more red than 3500K 80CRI.

From the samples I think 3000K 70CRI would be a good dedicated veg spectrum, also 4000K 70 or 80CRI. Any of them will get the job done but it wouldn't be intuitive to use 2700K 90CRI for instance, but it might make sense to use 3000K 70CRI full cycle. Regarding flowering and yield, I have no idea which is best. On paper 3000K 70CRI should provide the best yield (YPF) once the phosphor losses are factored in. In practice nobody seems to have shown one to be better grow after grow, Just different and conflicting reports.

20 par watts per foot from most any light source is going to do a really good/similar job. I prefer 3000K 90CRI but more because it seems like the ideal spectrum, rather than because of some guarantee it will work better. I don't care to have UV in my grow space and don't see the point in anything beyond 700nm except perhaps for lights out. If a lamp came with end of day functionality that would be a nice selling point. DIY there are various options for that and UV bulbs if UV is desired.

Why one of the cool kids hasn't built a blurple lamp and qualified it against white after all these years of people DIYing, I don't know. I guess there's a practicality to the design and build process that precludes building things one might not want to use after it's built, or would cost more than necessary to do the same job. Still, it's entirely possible to DIY a high efficiency 450+630+660 lamp and quantify the output to a high degree of accuracy.

Those flip chips did look promising....

Don't you think for DIY lights no blue is needed if you use white ?

 

[InTheValley]

A lot of people would like to see you run that side by side, either equal par map or wattage -vs- white and post final yield numbers. I've been hoping someone would do it for years. People with crappy blurple lamps generally don't have nice par meters.

Yeah, maybe i could do that. I need another spot tho. Im just early vegging this, on day 24 from seed. Its mainly under this light for 8 hours, just to keep her in veg state, then the other 8 under my cobs. but with this one, im going to top top top top top top top the crap out till i flip. topped the first top yesterday, and going to top all the others in a few days, need a top to clone for sex. but im running outta room and will defoliate her after the next topping sesh.

this is Sequoia Shipwreck, at 23 days from seed, 517PAR @ 26 inches, 125watts( hydrofarm par meter,

 

[InTheValley]

i havent even given her any nutes yet, starting tomorrow, megacrop only. topped after the 5th node.

 

[Rahz]

Those flip chips did look promising....

Don't you think for DIY lights no blue is needed if you use white ?

Yea, even with something like 2700K 90CRI there is enough blue. Those flip chips come in white and blue/red now. The blue/red has like, 5 different options from 10%Blue/90%Red to 50/50. Same company is the one building the 2400w cobs. Interesting designs, just not cutting edge diodes being used.

 

[Rahz]

i havent even given her any nutes yet, starting tomorrow, megacrop only. topped after the 5th node.

I've thought about trying Megacrop. How many grams do you use in a gallon during mid flower? I've played around with the numbers. 4g Megacrop + .5g Koolbloom comes out to 100/50/150 which is the same as I get with 2.5g Maxigro + 2.5g Maxibloom. I like the fact that it has Silica in it. One less bottle/product.

 

[Randomblame]

It varies. Flip Chip for instance allows you to choose what percentage of blue and red you want in your cobs. If they were even close to Samsung, Vero29C, Citizen etc. in terms of efficiency they would be worth taking a look at.

@Randomblame does make a very good point though. It prompted me to dig up some old data and look at it again. I've arranged it into a summary chart.

View attachment 4227308

Rows 3-5 - spectral analysis
Row 7 - Raw PPFD readings
Row 8 - Raw readings with Mcree correction factor.
Rows 10, 13, 16 - Relative intensity: % * raw reading / 100
Rows 11, 14, 17 - (10, 13, 16) with Mcree correction factor.


It would have been nice if 4000K 80CRI had been included in the mix, but we can predict with some degree of accuracy the values based on the available data. This wouldn't be true of 5000+ because the spectral curves become very different. If we extrapolate 4000K 80CRI from the data the Blue/Green/Red %s would be around 16.5/46/37.5. PPFD reading would be about 936 and with Mcree correction it wouldn't be much different than 3000K 80CRI or 3500K 80CRI.

CRI- 80CRI provides about 10% red (600-700nm) boost over 70CRI. 90CRI provides about 10% red boost over 80CRI. CRI has a minor impact on blue output. This is all at the expense of the 500-600nm regions. 3000K 70CRI Has the highest par readings by far. Even when a correction factor based on the Mcree curve is applied 3000K 70 CRI still has the highest score due to all the light in the 500-600 region. The sample with the highest R + B is 3000K 90CRI.

K- Blue levels drop about 40% going from 3000K to 2700K. Blue levels increase by about 15% from 3000 to 3500K. 2700K has a slight increase over 3000K in red. 3000K 80CRI has around 8% more red than 3500K 80CRI.

From the samples I think 3000K 70CRI would be a good dedicated veg spectrum, also 4000K 70 or 80CRI. Any of them will get the job done but it wouldn't be intuitive to use 2700K 90CRI for instance, but it might make sense to use 3000K 70CRI full cycle. Regarding flowering and yield, I have no idea which is best. On paper 3000K 70CRI should provide the best yield (YPF) once the phosphor losses are factored in. In practice nobody seems to have shown one to be better grow after grow, Just different and conflicting reports.

20 par watts per foot from most any light source is going to do a really good/similar job. I prefer 3000K 90CRI but more because it seems like the ideal spectrum, rather than because of some guarantee it will work better. I don't care to have UV in my grow space and don't see the point in anything beyond 700nm except perhaps for lights out. If a lamp came with end of day functionality that would be a nice selling point. DIY there are various options for that and UV bulbs if UV is desired.

Why one of the cool kids hasn't built a blurple lamp and qualified it against white after all these years of people DIYing, I don't know. I guess there's a practicality to the design and build process that precludes building things one might not want to use after it's built, or would cost more than necessary to do the same job. Still, it's entirely possible to DIY a high efficiency 450+630+660 lamp and quantify the output to a high degree of accuracy.

The problem with most blurples is they don't use top bins only. The Unitfarm in a good example. They use Cree XP-E but not the HE series. Even Osram used only T3 for their Zelion lights. The only top bin blurple fixture I know is made from SanLight, austria; 2,7μMol/j and these lights do a pretty good job! But they are more familiar in german-speaking countries and in europe and these lights are f...ng expensive. 140w 3ft. bars ~440€ and 2 89% eff. Recom drivers, not even dimmable, no far-red and their latest generation looks finally like warm white not blurple.
Below is a datasheet of the latest generation S4W bars if interested.

Integrated flower trigger is a key feature for me and can also be used to add a certain amount of far-red when lights on when strong enough. This way you get even more control over the stretch for instance(another way to comunicate).
An example for its usage are indika strains. They stay extremely compact with LED and a bit more far-red helps to get a bit more nodial stretch without getting skinny stems.
A bit far-red is also helpful for other mechanisms like shortening the flower cycle, switching phytochrome far-red, increased leaf temps, emerson effect and it helps to even out the excitation states between PS-I and II which makes the whole PS process more efficient.
My flower-trigger has only around 20μMol/s(6 top bin XP-E's at 600mA + Sonoff timer, ~8,5sft area) and this little amount can already have a strong effect. CRI90 already has twice as much far-red like CRI80 and the most strains react in a positive way.
From my POV each LED lamp should have such a separate flower-trigger/FR-booster because there are many more useful effects than just shortening the night length.

 

[InTheValley]

I've thought about trying Megacrop. How many grams do you use in a gallon during mid flower? I've played around with the numbers. 4g Megacrop + .5g Koolbloom comes out to 100/50/150 which is the same as I get with 2.5g Maxigro + 2.5g Maxibloom. I like the fact that it has Silica in it. One less bottle/product.

just tryd 6g pergallon at 24 days in flower, and she didnt care for it, calls for 5 at this stage, i wanted to see her thresold. im going to go with 4g now.

 

[Humple]

i have 1, thats how. I have the Mini version, and its a pretty dam good light, just not big enough for my 3x3, hits 1000PAR at 16 inches under the center,

What are the readings on the perimeter?

 

[InTheValley]

What are the readings on the perimeter?

from the center to the outter edge of light, there is a 50% drop off. For every 1inche after that, loses about 50 par. The further down, drop off is a bit less then higher up, of course @ 50% total from center to edge of 2x2. that makes sense, so at 21 inches seems to be the sweet spot for best coverage from center to edge most uniformly at 600 par center 300 par edge of a 2x2 area. would be decent in a 2x2, especially if you can move it around during the day.

 

[InTheValley]

and for all BS aside, for $288 your better off getting 2x Mars300 and putting lenses in them. $160 bucks, with lens.. Cant remember what it was, like 1000 PAR at 32 inches,

 

[sethimus]

The problem with most blurples is they don't use top bins only. The Unitfarm in a good example. They use Cree XP-E but not the HE series. Even Osram used only T3 for their Zelion lights. The only top bin blurple fixture I know is made from SanLight, austria; 2,7μMol/j and these lights do a pretty good job! But they are more familiar in german-speaking countries and in europe and these lights are f...ng expensive. 140w 3ft. bars ~440€ and 2 89% eff. Recom drivers, not even dimmable, no far-red and their latest generation looks finally like warm white not blurple.
Below is a datasheet of the latest generation S4W bars if interested.

Integrated flower trigger is a key feature for me and can also be used to add a certain amount of far-red when lights on when strong enough. This way you get even more control over the stretch for instance(another way to comunicate).
An example for its usage are indika strains. They stay extremely compact with LED and a bit more far-red helps to get a bit more nodial stretch without getting skinny stems.
A bit far-red is also helpful for other mechanisms like shortening the flower cycle, switching phytochrome far-red, increased leaf temps, emerson effect and it helps to even out the excitation states between PS-I and II which makes the whole PS process more efficient.
My flower-trigger has only around 20μMol/s(6 top bin XP-E's at 600mA + Sonoff timer, ~8,5sft area) and this little amount can already have a strong effect. CRI90 already has twice as much far-red like CRI80 and the most strains react in a positive way.
From my POV each LED lamp should have such a separate flower-trigger/FR-booster because there are many more useful effects than just shortening the night length.

sanlight is white + red, not something i would consider a "blurple" light?

 

[wietefras]

For that matter, a really crappy blurple light would work fine for testing spectrum -vs- spectrum. Stick a good par meter in there. Dial it in so the readings are the same as a white test area. Grow and examine results.

That would provide information on whether blurple is worth pursuing.

This has already been done and purple was shown to be more efficient than warm white. Also, the warmer the white, it was also more efficient. IIRC there was about 5% difference between purple and 4000K (with 2700K and 3000K in between)

Indeed with same intensities and not accounting for efficiency of the lights themselves.

 

[Aolelon]

I've thought about trying Megacrop. How many grams do you use in a gallon during mid flower? I've played around with the numbers. 4g Megacrop + .5g Koolbloom comes out to 100/50/150 which is the same as I get with 2.5g Maxigro + 2.5g Maxibloom. I like the fact that it has Silica in it. One less bottle/product.

I just grew with megacrop and it's the cats meow man. Plants were extremely healthy all the way through. I was using 5.5g mid flower till harvest, may have been just a little too much nitro, so I would honestly play around 4.5g-5.5g at this stage. I added a little bit of protekt in the beginning, but I didnt need to add any calmag to my r/o water at all.