Why do some want high CRI?

[hicpic]

Mouser actually expects a batch of the top bin (BD) 3000K/90CRI CXB3590 at the end of October. The price is terrible but they should match their lower CRI counterparts in efficiency. All the data and the design are stolen from your spreadsheets
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Why is BD "top bin"? On the spec sheet the 3500k CB has more minimum flux. Am I missing something?

Im still trying to decide the LED that Im going to be using. I was looking for info on if CRI would make any diffrence. If not, the 4000k of the CXB3590 seems to be a good contender. It seems to be the highest flux chip of either the 3000k, 3500k, or 4000k. But its CRI is the lowest at 70. If an HPS has only a 22, it can't matter that much right?

http://www.cree.com/~/media/Files/Cree/LED-Components-and-Modules/XLamp/Data-and-Binning/ds-CXB3590.pdf

 

[alesh]

Why is BD "top bin"? On the spec sheet the 3500k CB has more minimum flux. Am I missing something?

Im still trying to decide the LED that Im going to be using. I was looking for info on if CRI would make any diffrence. If not, the 4000k of the CXB3590 seems to be a good contender. It seems to be the highest flux chip of either the 3000k, 3500k, or 4000k. But its CRI is the lowest at 70. If an HPS has only a 22, it can't matter that much right?

http://www.cree.com/~/media/Files/Cree/LED-Components-and-Modules/XLamp/Data-and-Binning/ds-CXB3590.pdf

BD is the top bin for 90CRI 3000K.

And don't forget that lumens are for humans

 

[hicpic]

Hi CRi leds (~95 CRi) have a more even spectral balance and they have a larger percentage of their output in the deep red range where human vision response is low. It is a slightly more photosynthetically efficient spectrum BUT it comes at a significant cost to efficiency. 70-80CRi LEDs seems to be a good compromise point of very high efficiency, good output in the red/deep red range and high efficiency.

To make matters worse for the high CRi option, we do not currently have access to top bins of the high CRi but we do have access to the top bin 3000K and 3500K 80 CRi.

The curves have been adjusted (thank you @MrFlux ) so they are truly relative to each other in terms of flux, assuming top bins of each.
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Where did you get that chart? I would love to read the source material around it.

BD is the top bin for 90CRI 3000K.

And don't forget that lumens are for humans
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Ah, I was looking at the 3000k as a whole, not just the 90CRI 3000k. Makes sense now, thanks for the clarification. Can you like that spread sheets source? I would love to look at it in more depth.

 

[alesh]

Where did you get that chart? I would love to read the source material around it.



Ah, I was looking at the 3000k as a whole, not just the 90CRI 3000k. Makes sense now, thanks for the clarification. Can you like that spread sheets source? I would love to look at it in more depth.

The first one was done by @SupraSPL the second one by me (but I just used Supra's data). And if I am not mistaken, the chart from Supra's post was made by MrFlux.

 

[SupraSPL]

That is correct, from this thread, although I think Mr Flux adjusted some of his LER numbers slightly later on
https://www.rollitup.org/t/cree-cxa-analysis.743645/

It helps expose the unintentionally misleading SPD graphs posted in Manufacturer spec sheets. They simply line up the highest peak at 100%, the curves are not relative to each other.

 

[ttystikk]

And just to fill in an additional detail, don't try to run the 860W CDM lamp on the Platinum ballast; a company tried to make a digital ballast specifically for the 860W bulb and they went out of business. The lamps couldn't take it and had a very high failure rate. Apparently this phenomenon is the explanation for why the 315W CMH isn't any bigger than it is.

Lol, what a difference a few months makes! Turns out this combo works tits for the 860W CDM Allstart, @dbkick proved it!

Not just a BS talker here:
In all her glory - money where my mouth is lol

Note the free Super HPS Lamp as well. Helps offset the "cost" of this badboy when compared to other high end ballasts

View attachment 3531502

I bet it works pretty good- and I'll bet you had a nasty surprise when you tried to order another one, because they're discontinued.

I'm getting a LFSW thouie ballast from @Revolution Micro and I'll be cranking this very combo up to see what she'll do.

I'll even compare to top shelf COB LED.

 

[dbkick]

Y tHE wAY

Lol, what a difference a few months makes! Turns out this combo works tits for the 860W CDM Allstart, @dbkick proved it!



I bet it works pretty good- and I'll bet you had a nasty surprise when you tried to order another one, because they're discontinued.

I'm getting a LFSW thouie ballast from @Revolution Micro and I'll be cranking this very combo up to see what she'll do.

I'll even compare to top shelf COB LED.

what disocontnuesd? I'm WASTED, BY tHE wAY

 

[ttystikk]

Y tHE wAY
what disocontnuesd? I'm WASTED, BY tHE wAY

Both the Horti Platinum and the 860W Allstart.

 

[dbkick]

Both the Horti Platinum and the 860W Allstart.

haven't the just replaced the bt37 with th e wasteful bt56 brother tty? they've just replaced it with the bt37 outer envelope instead of the bt56./
I've been the bt56 discontinued but have not seen a thing about the bt37.

 

[dbkick]

facked up.

 

[Hybridway]

Has this been verified with a spectrometer?
When you state "The more even the spectral output", is the spectral output in the range of what benefits photosynthesis more than visual appeal?
These lights are designed for producing "good looking" light, not for the spectrum the plants may need. Maybe my point is "does it benefit the plant, either from increased rate of photosynthesis - or more compact plants, higher yield of flowers, higher yield of resin, increased THC / CBD content... more nutritious vegetables...

The earliest LED (tungsten screw in replacement for lamps) had poor CRI when dimmed - I think reviews said the light became blue. If we are not running our COB's at full power, then are they dimmed?

Curious, not attacking, just want to understand.

Yes, increased photosynthesis is what I saw from my 95 CRI Amare LED.
Stupendous growth. I'm an HPS / MH grower & know the differance.
Also compared that high CRI to a primarily R+B w/ enough green to be RQE , LED. The Amare must've yeilded 4x more by the looks of the rack. Actually looks like allot more then that.
Growers around me have yeilded a lb. off of the 315 CMH @ 92 CRI.
I am positive the high CRI is deffinetly very beneficial to our plants growth, development, Yeild, potency, ect.....
But yes, we do very well using low CRI HPS bulbs.
I feel we can achieve similiar results in weight using a high CRI led or CMH at a low wattage.
High CRI cobs are now pretty inefficient in comparison to lower CRI cobs. So, the added colored monochrome colors allow for the high CRI & matched efficiency to the lower CRI cobs, yet still achieving a very high CRI from the LES.
I suggest trying it to see for yourself. I didn't believe it until I tried myself.
Harvested & am still trimming. But I'm willing to bet my high CRI AMARE led matched my 1200 w of HPS in a 4'x4' area, or at the least, very close w/ only 450 w & very minimal cooling needed.
I noticed more overall growth from my plants in every way.

 

[alesh]

Just visited a friend I had made a few lamps for. No hard data, but so far 3000K 90CRI BD > 3500K 80CRI CD. The differences are minimal, though.

 

[Bestg4202]

View attachment 3515787

Hi I know this is old....but if your still around I was curious if this graph is an accurate comparison ,in terms of spectral photon flux, to the 1st one posted a few posts back where you were displaying the difference in spectral distribution. I only ask because this would show the Vero as being much more efficient in this regard. (if I understand correctly that is. Lol. )

 

[cogitech]

Important to keep in mind that the chart posted on the first page can only be used to judge the specific lights in question. To extrapolate and conclude that 80 CRI is better in all cases would be an error. I'm not saying anyone has done that, just warning that the results shown are not always going to be the case with different LEDs.

An example:

I decided I wanted 3500k COBs as "all purpose" (veg and flower) lights, and I wanted to keep cost down so I decided to go with Citizen 1212s.

I looked at the spectral output of the 80 and 90 CRI COBs:


Then I looked at the absorption rate of PAR spectrum:

The 3500k 90 CRI has a distinct advantage over the 3500k 80 CRI, in both the 450nm and (especially) 680nm area. The choice was easy.

Granted, the 80 CRI light puts out about 25 more lm/w, but my setup will already have more light than it needs and I have pretty affordable electricity, so it wasn't a factor for me.

 

[Bestg4202]

Important to keep in mind that the chart posted on the first page can only be used to judge the specific lights in question. To extrapolate and conclude that 80 CRI is better in all cases would be an error. I'm not saying anyone has done that, just warning that the results shown are not always going to be the case with different LEDs.

An example:

I decided I wanted 3500k COBs as "all purpose" (veg and flower) lights, and I wanted to keep cost down so I decided to go with Citizen 1212s.

I looked at the spectral output of the 80 and 90 CRI COBs:

View attachment 4136974
Then I looked at the absorption rate of PAR spectrum:
View attachment 4136975

The 90 CRI has a distinct advantage in both the 450nm and 680nm area. The choice was easy.

Granted, the 80 CRI light puts out about 25 more lm/w, but my setup will already have more light than it needs and I have pretty affordable electricity, so it wasn't a factor for me.

Im about to purchase new lights and it's down to 3 choices...2 are Vero 29's so that graph with the Vero 29"s caught my attention. But I don't have any other vero29 graphs to compare it too. Is there someplace to find that kind of info?

 

[cogitech]

Im about to purchase new lights and it's down to 3 choices...2 are Vero 29's so that graph with the Vero 29"s caught my attention. But I don't have any other vero29 graphs to compare it too. Is there someplace to find that kind of info?

Not sure about other manufacturers, but the datasheets for the Citizens were dead easy to find with google. Good luck.

 

[alesh]

Hi I know this is old....but if your still around I was curious if this graph is an accurate comparison ,in terms of spectral photon flux, to the 1st one posted a few posts back where you were displaying the difference in spectral distribution. I only ask because this would show the Vero as being much more efficient in this regard. (if I understand correctly that is. Lol. )

It's old and no longer valid with newer Veros. I'd go with higher CRI nowadays.

 

[ttystikk]

I'll tell you right now that the death knell has already sounded for single ended HPS and MH... and CMH/CDM and DE will only get another few year's reprieve. Their replacement has arrived, become cost competitive and now it's only a matter of time.

COB LED really is better and once the word gets out about just how good they are, a growroom designer's job won't include deciding whether to buy LED over HID; it will simply be deciding which LED chips to use and how many to get the desired ratio between up front cost and operating efficiency.

A three year old Post above; just thought I'd say, 'I told you so!'.