CRI test and Mcree weighted results

Johnnycannaseed1

Well-Known Member
The point is in this quote from Greengenes:
In the Netherlands there have been several of these tests done with the same outcome. Spectral distribution hardly had any effect on yield. It affects internode length and number of leafs and such, but hardly the yield.

Then again, this needs to be within reason, because if the morphology gets too bad it will start to affect yields. Which is why we don't flower under 5000K even if that would put even more light on the plants.
And right there where you have contradictied yourself, right between those two posts, you, Greengene and every other cherry picking expert have clearly demonstrated the point of the importance of spectrum ...but worse still that you cannot even recognise this "FACT":clap:

Satived was bang on when he said the evidence could be presented to you but you would still "FAIL" to recognise the truth... your post says it all...But keep on following and quoting the so called expert emperors haha!!!
 
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Johnnycannaseed1

Well-Known Member
I noticed this, too- to the point where I converted my entire lab to cdm/cmh lighting and won't use HPS anymore.
At least you are on it lol.

Shame about one or two in here (especially because they make bold claims about being expert growers who have grown for x years blah blah blah) ...who are so stuck on stupid, blindly following industry trends quoting garbage to make themselves look smart ....Yet they are totally unable to see the wood for the trees in light of the evidence...

But heck what would I know, I must have been imagining the differences I was seeing!!!
 
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JorgeGonzales

Well-Known Member
However, due to Stokes losses, the PAR levels for high CRI and warmer color temperatures will generally be less than on lower CRI and/or colder color temperatures.
You are confusing energy loss with photon loss and making false assumptions about phosphor efficiency and how it relates to CRI and CCT. You have spent too long thinking in terms of lumens, which follow that pattern for obvious reasons.

Here is an older chart from Citizen. You won't find a pattern here that matches your assumptions, because phosphor quantum yield is basically formula dependent:

image.jpg
 

wietefras

Well-Known Member
And right there where you have contradictied yourself between those two posts
Nope.

What do you think "within reason" means? I'd say it means that small differences are fine and big differences (might) not. I actually literately explained that in my post

Cherry pick much?

Satived was bang on when he said the evidence could be presented to you but you would still "FAIL" to recognise the truth... your post says it all...But keep on following and quoting the so called expert emperors haha!!!
The evidence was presented to you two, but the cognitive dissonance prevents you from understanding it.

Here let me help you by posting it again. it's a quote from an actual scientist called Bruce Bugbee rather than some bloke from Reddit:
CONCLUSIONS
Differences in radiation quality from the six most common electric lamps have little effect on photosynthetic rate. Radiation quality primarily alters growth because of changes in branching or internode elongation, which change radiation absorption.
http://biology.mcgill.ca/Phytotron/LightWkshp1994/1.5 Bugbee/Bugbee text.htm[/QUOTE]
So if you are saying there is more than McCree then you are sort of right, but the effect is proven to be exactly the opposite of what you are dreaming.

..canna grown under a white spectrum generally produces better quality bud than canna under Hps
Growers who grow under MH say that extra UV and more blue from it's spectrum gives them more potent weed. Which also bodes well for colder color temperatures rather than warmer. So again you shoot yourself in the foot with your vague claims.

Still, I wouldn't claim either of those are true. I'm not so stupid that I'd present my assumptions/beliefs as facts. All I can do is point out that:
1) There is overwhelming evidence from scientific research that spectral distributions simply aren't that relevant for yields and that the quantity of light is more important
1) There is a clear PAR advantage from lower CRI over higher CRI and from warmer color temperatures over colder
and 1+1=2
 

Johnnycannaseed1

Well-Known Member
You have just shown proof of your dissonance as I have quoted... even now you completely fail to recognise the importance of spectrum even though you have previously admitted it... too funny lmao... Yeah you stick to reading rather than "Actually Growing" and keep wandering around in circles haha!!!
 

Stephenj37826

Well-Known Member
Nope.

What do you think "within reason" means? I'd say it means that small differences are fine and big differences (might) not. I actually literately explained that in my post

Cherry pick much?

The evidence was presented to you two, but the cognitive dissonance prevents you from understanding it.

Here let me help you by posting it again. it's a quote from an actual scientist called Bruce Bugbee rather than some bloke from Reddit:


So if you are saying there is more than McCree then you are sort of right, but the effect is proven to be exactly the opposite of what you are dreaming.


Growers who grow under MH say that extra UV and more blue from it's spectrum gives them more potent weed. Which also bodes well for colder color temperatures rather than warmer. So again you shoot yourself in the foot with your vague claims.

Still, I wouldn't claim either of those are true. I'm not so stupid that I'd present my assumptions/beliefs as facts. All I can do is point out that:
1) There is overwhelming evidence from scientific research that spectral distributions simply aren't that relevant for yields and that the quantity of light is more important
1) There is a clear PAR advantage from lower CRI over higher CRI and from warmer color temperatures over colder
and 1+1=2
I personally still want to see the side by sides as I believe that THE Emerson effect works well past 700nm.... so either Mcree is correct or Emerson is. Did mcree test with combinations of wavelengths? Emerson effect works best with ~ 8:1 ratio with a 60 nm split. So 660 should be 8x what 720 is for optimum results. Well 90cri 3000k citi seems to be pretty darn close.
 

ttystikk

Well-Known Member
I'm curious about the extent to which we're engaged in a hair splitting contest here; no one disagrees that just about any color temp or CRI score of COB LED will grow good cannabis, the debate is more about 'best' rather than mere adequacy.

There was a big quality improvement from HPS to CDM/CMH, and again when I switched to COB LED (Cree 3590 3500K 80CRI).

When optimizing the chip's spectrum, would I expect better quality or more yield compared to the chip I'm running now?
 

Shugglet

Well-Known Member
When optimizing the chip's spectrum, would I expect better quality or more yield compared to the chip I'm running now?
And therein lies the question, what is "optimal"? Some people would prefer yield vs quality. But regardless "quality" is subjective.

Then its a matter of what kind of impact (if any) spectrum has on those qualities. A major pain in the ass to test.

Then theres the whole matter of whether different strains react differently to differing spectra.
 

Sativied

Well-Known Member
It isn't funny but your comment sure makes it seem funny Lmao:lol:
Yes sometimes the difference between tragedy and comedy is a very thin line... or more like a grey area. Seeing several people blindly pick 1750ma drivers because wietefras decided that is best to do is funny but sad at the same time.

Riu is usually more entertaining. Like Jorge arguing pro-high blue because he read blue affects stomata regulation. That just cracks me up. Or even better, Rahz posting about morphology. Search the forums for user @Rahz and search term "morphology", note the dates, then do the same for my username. Slapstick comical. It's a level below the level of P is flowering so more P is more flower...

Or how about gg referring to info from Heliospectra above who provide similar general indoor spectra like osram, philips, and like cree suggested.
image.png

the obvious way to go about indoor growing for any horticulturist (WR or WBR) unless one has a specific scientifically proven extra-ordinary best cannabis spectrum. Doesn't look much like cree 3500k 80cri to me.

I think its more a photon vs spectrum camp.
Funny fact the members of the photon camp have allot of real time hard data to present. Data about Weed!
While the spectrum camp is still figuring out what spectrum to choose and have allot of theory data. About tomato and Cucumis sativus(cucumber)
That's all just what the 3500k-datasheet-efficiency camp die-hards and some people projecting the illusion of knowledge want others to believe. Spectrum does not dictate photon output. High and efficient input and more optimal spectrum are not mutually exclusive. Rahz's commercial lights are not more efficient than my light is, neither is wietefras' setup of 3000k at 1750...

Apparently, you can have both and cooler 80 cri cobs won't make them more efficient by default. Apparently, they rather sacrifice spectrum to pretend that is efficient instead of at most economical, but then they don't buy the cheapest cobs either... They don't run maximum efficiency, they don't run maximum intensity, they don't endlessly wait for the next more efficient led. All their nonsense in this discussion is just one big fallacy. Letting efficiency dictate spectrum while it is influenced to a much larger extend by other factors is just foolish.

You know what else exists in theory? Gravity. Just like the influence of blue light on auxins and indirectly ethylene and thus flower production it's quite real in practice too. Same for anthocyanin production, blue being great to induce photoinhibition, green resulting in shade avoidance like FR but without the advantage of FR... which too goes further than what some self-proclaimed experts here read about emerson effect. Fyi most plants operate very much in the same way in many aspects, in theory and in practice...It's ironically the 3500k camp that cherrypicks specific spectrum theory to get to their numbers, claiming to know what's best for cannabis, while ignoring and defying all the other botany that would show how silly they are. Which doesn't even conflict with mccree curves, just with their own biased conclusion. In practice, there's just a lot more to it.
 

PhotonFUD

Well-Known Member
I'm curious about the extent to which we're engaged in a hair splitting contest here; no one disagrees that just about any color temp or CRI score of COB LED will grow good cannabis, the debate is more about 'best' rather than mere adequacy.

There was a big quality improvement from HPS to CDM/CMH, and again when I switched to COB LED (Cree 3590 3500K 80CRI).

When optimizing the chip's spectrum, would I expect better quality or more yield compared to the chip I'm running now?

Plants will use any light available to them. Research has found that photosynthesis uses 700nm photons and that plants condition absorbed photons of shorter wavelengths. If you are asking for 'best' then you would be in a good position to go with the option that provides the most photons in the 600-700nm region.

Some other things to consider:
Intensity - research has found that plants absorb at max ~1/5, or ~400umoles, of PAR spectrum from sunlight
Uniformity - making light energy at the same intensity available to more of the plant maximizing photosynthetic potential thus increasing overall efficiency
Environmental - factors such as thermal management that can help improve the use of available light by both the plant and light source systems

Best also could be an order of magnitude higher than acceptable.
 

Rahz

Well-Known Member
Mcree factor for Hortilux Super HPS: 79.457

I picked the Super HPS because it has a familiar SPD. Despite not having a lot of red it scores well because of the high levels of orange.

Every brand and model of bulb will have a different spectrum. I'm not going to digitize every SPD out there, but if someone want's to give me the values for a spectrum from 400-700 I'll be glad to provide the Mcree factor, or I will be glad to share the spreadsheet with the Mcree values in it.
 

Rahz

Well-Known Member
Rahz posting about morphology. Search the forums for user @Rahz and search term "morphology", note the dates, then do the same for my username
All about you isn't it?

And this:

Funny how selective you are repeating the facts I posted
From my response to:

So why do red bias Leds fall down especially compared to an old skool "green yellow" hps... is that not contrary to McCree data?
He asked about the relationship between LED/HPS and Mcree. I answered with a correct prediction. What else could I have said? It has nothing to do with anything you might have mentioned in the past. Why you think it does I have no idea, except a hyper inflated sense of self importance. The world will spin without you.

Anyway, I've bothered to correspond with you. Instead of replying to what I've said directly to you, you ignore it and find something else snarky to say. Why is that? Oh, because your initial reply to me made you look like a fool and you're ignoring it hoping it will just go away. Let me remind you again. You accused me of reeking of bias towards 3500K when the test results clearly did not. It was an ignorant statement on your part and your attitude delivered it poorly. Did you even read the test results this post is based on? I asked you that already and you failed to answer. I suspect you will do so again. You will pick on whatever comments you can find that you think might make yourself look good and ignore everything else that doesn't. I can only assume your goal here is to make yourself feel good by diminishing others.
 

Greengenes707

Well-Known Member
@Johnnycannaseed1
You should take your own advise...just cause you type it doesn't make it true.

I just gave you a mountain of data to help you understand McCree and yet you still have no idea or even try.

So I am going to take you" no...you are" response as a, NO, you don't have any results or grows to show.

So you can keep typing to yourself that I am wrong, while I give you proof of everything you misunderstand in hard facts. I can lead you to the water, but your the one how's not drinking. Thankfully I couldn't give two fucks about if you drink or dehydrate.

You have no data, no grows, and a half century of data and scientifically accepted papers opposing you. Sure bro...kill the messenger who made you realize how far off you are.

PS...when you bring up the "better grow more bro" comment...you should sure as hell have some grows of your own to drop...specially when your wrong unless you have "your own" proof.

Have fun children.
 

SSGrower

Well-Known Member
Yes, well 5 way grow off. Results will be in early next year.
Those are the meters you want to use. :bigjoint:

What I know is this trying to use a single sensor to evaluate output is great to compare like objects but wide range sensors tend to be weighted, but they are not weighted to the output of the sun but rather a human construct like the mcree curve. My experience with these types of meters is limited to uv curing and human needs. IMO weighting to PAR neglects negative impact of too much of x, y, or z.

I'm a hobbyist do in this for fun and smoke.
 

Johnnycannaseed1

Well-Known Member
Aww stop being a cry baby... You are just sulking because you are not the know it all you thought you were:lol:

I am going to make a thread here later on today just for you, but I must apologise in advance for it being a tomato one lol;)
 

Greengenes707

Well-Known Member
Aww stop being a cry baby... You are just sulking because you are not the know it all you thought you were:lol:

I am going to make a thread here later on today just for you, but I must apologise in advance for it being a tomato one lol;)
So that's a no on the grows?
And a no on any proof of me "not knowing what I thought"...just childish "no you are" comebacks???

Seriously dude...do you have anything? I have already countered everything in your first post and shown it to be wrong. Please show some evidence, even studies stating your claims??? You have presented nothing.
 
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