JorgeGonzales
Well-Known Member
I'm not reading specs or using Supra's spreadsheets. You really don't understand how this stuff works. At all.
3500k vs 4000k vs 5000k ?
- Thread starter Trippyness
- Start date
Rahz
Well-Known Member
3000, 3500K I've used them both. I can't say one is clearly better than the other in any respect. Even from a vegetative vantage point I wouldn't feel bad sticking plants under a 3000K led spectrum.
The Mcree study is showing a strong "red" response from 620-680. 3500K peak is a little to the left of that but the concern when moving the peak higher is output beyond 700 is also going up, that's why I would ultimately like to see the peak closer to 630, but not 660. Relative spectral power of 680nm in the 3500K profile is already enough to drive the Emerson effect. 3500K works well in practice and in theory the curve looks really nice.
That being said, I will be taking a closer look at the 3000K 90 CRI options in the future. If the CRI is being raised without bulking up the green then all that's left to question is efficiency.
The Mcree study is showing a strong "red" response from 620-680. 3500K peak is a little to the left of that but the concern when moving the peak higher is output beyond 700 is also going up, that's why I would ultimately like to see the peak closer to 630, but not 660. Relative spectral power of 680nm in the 3500K profile is already enough to drive the Emerson effect. 3500K works well in practice and in theory the curve looks really nice.
That being said, I will be taking a closer look at the 3000K 90 CRI options in the future. If the CRI is being raised without bulking up the green then all that's left to question is efficiency.
JorgeGonzales
Well-Known Member
You lose green, and gain blue and red. Which is partially why the lm/W drops. See this post https://www.rollitup.org/t/3500k-vs-4000k-vs-5000k.910643/page-8#post-12648976 if it got lost in the noise.
JorgeGonzales
Well-Known Member
And if you trust digitized SPD data cross referenced with manufacturer provided lm/W, efficiency looks like a won battle too. Citizens appear to be the same price, no idea if Cree is easy to come by or cost effective. I don't know where anybody buys this stuff.
Sativied
Well-Known Member
Ppfd is a choice and limited. You probably mean ppf. Return to page 2 or 3, do not pass start.I literally just did the math to show how efficiency relates to ppfd. Now I feel like you're too high for this thread.
You're welcome too buddy lol
wow such expert... such colors...
Good luck trying to repair that ego. "This stuff" lol... I meant what I said about people rather not getting butthurt but your transparent childish response is somewhat entertaining/enjoyable. Don't worry, I'm done, for now. Thanks for uhm... 'participating' in this discussion.
Next time on Sativied vs LED Cult:
"Diy cob or 2.6μmol/s per watt affordable quality fixture with optimized spectrum."
Just kidding...
or am I...
Rahz
Well-Known Member
Not lost, very interesting chart, one of several posts that have peaked my interest. Not the same as CXA https://www.rollitup.org/t/cree-cxa-analysis.743645/
If 3000K 90CRI is hitting the spectrum peaks right with no loss to it's 80CRI counterpart then it may very well contend with 3500K for top spot. I'll mention again as it hasn't been brought up a lot, (preface by saying I understand photosynthesis doesn't stop at 700) it could be considered a flaw that the high CRI is beefier past 700. For instance your charts show a .7% increase in red along with a 3.4% increase in deep red.
Looking at the Mcree data, the response at 690 is similar to the response at 550 so it's worth taking into consideration.
JorgeGonzales
Well-Known Member
I don't want you to be done, but I suspect it's because you are in over your head and are tired of it being pointed out. You may not be debating, but you sure don't like being wrong.Ppfd is a choice and limited. You probably mean ppf. Return to page 2 or 3, do not pass start.
You're welcome too buddy lol
wow such expert... such colors...
Good luck trying to repair that ego. "This stuff" lol... I meant what I said about people rather not getting butthurt but your transparent childish response is somewhat entertaining/enjoyable. Don't worry, I'm done, for now. Thanks for uhm... 'participating' in this discussion.
Next time on Sativied vs LED Cult:
"Diy cob or 2.6μmol/s per watt affordable quality fixture with optimized spectrum."
Just kidding...
or am I...
I added a modest amount of original content while you again babbled on about LEDtards and Supra's spreadsheet. You can't tell the difference, or add anything to the discussion, or even tell which facts support your argument or not. None of this would matter if you didn't clog up threads with your nonsense. If I read the word "butthurt" one more time I'm going to claw my eyes out. What grade are you in again?
I'll let you in on a secret: your indiscriminate derision doesn't hide your ignorance, it only makes it that much more distasteful. Apparently it works for you as a self-defense mechanism, so rock on pal. Too bad it prevents you from learning.
optzulu
Well-Known Member
Yes but I can get the clu048-1212 cri70 in my country but in a tray of 30pieces. So i need to choose I want to get 2 trays one 3k and one 4k. Going to run them at 700ma I want to use them for a veg room and bloom room. Maybe 20/10 10/20 so why not cri70 ?
@Sativied
If I understand, you say its more importent what the plant can absorb and use tho grow then the lumens you throw at them ? We ppl are to much hunting the epeen and gr/w ratio and we get distracted.
Maybe you are right but I think the sun has the perfect ratio we want right ? Why does weed in afghanistan grow bigger then south france ? Intensity !! And thats what we do putting the highest intensity for thd best effi%
@Sativied
If I understand, you say its more importent what the plant can absorb and use tho grow then the lumens you throw at them ? We ppl are to much hunting the epeen and gr/w ratio and we get distracted.
Maybe you are right but I think the sun has the perfect ratio we want right ? Why does weed in afghanistan grow bigger then south france ? Intensity !! And thats what we do putting the highest intensity for thd best effi%
bullshit and I will quote you again.
... you bought and promote the wrong cobs ....
... For grow led however, it's just wrong...
... You are using the wrong cobs ...
... You're basically doing grow led all wrong...
... You're using the wrong cobs. Period.
These are not "suggestions" Problem is any warm white phosphor spectrum grows cannabis well and even cool whites will grow decently well. They can't be wrong cause it works.
Rahz
Well-Known Member
When we're talking about tuning K and CRI, consider neither of those values represents a specific spectral distribution. 70CRI with red peaking at 630 might be nice, who knows?
I think the good thing in this debate is that it's fully testable now. There may not be a 70CRI cob peaking at 630 but there are a lot of options and the use of monos can fill any missing areas. Efficiency taken into consideration and watts adjusted, anyone can now test 2 tents with the same umols and different spectrums.
Another good thing, 3500K, 3000K, 80, 90 CRI, they all look pretty good when put against the Mcree curve. I don't think there's a magical spectrum that produces amazing results compared to the others in the same ball park... they're all pretty magical. That said, I have an interest just like everyone else in finding out what is best, and from there to determine the relationship between deviance from it for increased photon count where possible. Despite various studies I think more technical data is necessary before those determinations are made. Ultimately I suspect a weighted version of the Mcree curve (not necessarily high CRI) will represent the perfect spectrum... just a guess.
I think the good thing in this debate is that it's fully testable now. There may not be a 70CRI cob peaking at 630 but there are a lot of options and the use of monos can fill any missing areas. Efficiency taken into consideration and watts adjusted, anyone can now test 2 tents with the same umols and different spectrums.
Another good thing, 3500K, 3000K, 80, 90 CRI, they all look pretty good when put against the Mcree curve. I don't think there's a magical spectrum that produces amazing results compared to the others in the same ball park... they're all pretty magical. That said, I have an interest just like everyone else in finding out what is best, and from there to determine the relationship between deviance from it for increased photon count where possible. Despite various studies I think more technical data is necessary before those determinations are made. Ultimately I suspect a weighted version of the Mcree curve (not necessarily high CRI) will represent the perfect spectrum... just a guess.
A 3500K or 3000K 70/80 cri plus a dash of deep reds and a sprinkle of actinic blues matches the McCree curve pretty darn well.
JorgeGonzales
Well-Known Member
I just thought it was cool that 90CRI cobs can produce higher PPF. That seems new.
It's interesting how much blue the Cree has at 3000K. 3500K looks nicer on the Citizen side. Haven't digitized the 3500K 80 CRI version, but this is ~2.38 umol/J @ 35W so probably about the same or higher.
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churchhaze
Well-Known Member
I just digitized the cxb3590 SPD charts and got LER of 327.69lm/W for 3000k 80cri and 276.72lm/W for 3000k 92cri.
At test current and temperature, the 3000k 80cri CB is 41% efficient while 3000k 92cri BD is 44% efficient. Whether the 92cri spectrum is better seems to be moot point. (top bins)
(not for PAR region, but whole spectrum. Efficiency when SPD truncated between 400-700 is 40% and 41%)
At test current and temperature, the 3000k 80cri CB is 41% efficient while 3000k 92cri BD is 44% efficient. Whether the 92cri spectrum is better seems to be moot point. (top bins)
(not for PAR region, but whole spectrum. Efficiency when SPD truncated between 400-700 is 40% and 41%)
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JorgeGonzales
Well-Known Member
I get 328 and 277, QER about 4.91 and 4.9, but I tend to trust alesh at his word. Unless I misunderstood and he was only talking about extra photons at 630nm or whatever.
mauricem00
Well-Known Member
I wonder if part of the problem is that plants can easily adapt to different environments and light sources so that actual comparisons between different light sources of similar radiometric efficiency ( light output in watts instead of lumens) produce inconclusive results.there seems to be a lot of conflicting data out there and light makers pick the study that makes their product look best. among high end (expensive) light makers there seems to be no agreement on the best spectrum. I think i'll stick with my T5s until they get this worked out and come out with a good affordable grow light and some consensus on the best spectrum. HIDs and T5s are proven technology but LEDs is still and evolving technology and many units on the market are a waste of money
alesh
Well-Known Member
Sure. I couldn't get export to csv working so it's in an excel spreadsheet...
alesh
Well-Known Member
Almost exactly same numbers I had come with.
The Green Griffin
Well-Known Member
Hey @Trippyness , if this post is too long let me know and I'll delete.
My perspective? Let me say right up front that my OPINIONS on LEDs are based on a lot of research, not RL grows. That said, I was trained as a scientist and (as any scientist will tell you) stage one in a research project is to consume as much of the existing documentation as possible, parse out what knowledge is backed by proper research and identify what current theories are, determine where the gaps are in the knowledge base, then design and test to fill the gaps or prove/ disprove the theories. You don't want to reinvent the wheel, but you do want to make sure that 'common knowledge' is based on fact. I'm in the first stage (for lighting), and will begin testing in a few months. My past grows were MH because I felt I got better stacking, higher THC and less stretch than my earlier runs with HPS, but that was prior to Gavita even being available and LEDs did not exist. I've been on hiatus from growing in order to earn a living.
Looks to me like the Amare will grow cannabis pretty well (as does most high intensity lighting), but they are making a LOT of assumptions about what they BELIEVE to be the right spectrum and light levels needed. As you see on this very thread, lots of members on this forum believe they know the (close to) perfect spectrum - and while each is different most are also extraordinarily effective at producing dank. As I said earlier, we may not know the perfect spectrum, but we sure as hell know that intensity is critical and have a pretty darn good idea of the spectrum needed - certainly enough to make great decisions about which light engines to use based on which of the trade offs are best for your circumstances.
This heated discussion about 3000k 90CRI vs 3500 80 CRI, etc. etc.? To use a racing analogy I truly feel we are tweaking the air to fuel ratio by a tiny amount to adjust for temperature, humidity and elevation differences. The car, the motor and the transmission are just fine, we are simply trying to shave a few tenths of a second off lap times. Our LED Porche will still outrun every HPS Buick ever built, as long there is a competent driver and an appropriate surface to run on. As an example of an inappropriate surface, even today I'd use Gavitas in a heartbeat for side lighting in a vertical garden due to its radiation pattern. Or if I HAD to maximize initial yield for the lowest possible capital investment - which is very short term thinking ( it will reduce long term profit) but could be necessary or appropriate depending upon the business plan.
Nearly all of the discussion here is based on speculation and theory. Well informed and in most cases logical, but theory nonetheless. When a grower finds something that works well for them, they naturally migrate to it even if they haven't 'proven' it with extensive, repeatable testing. That does not mean they are wrong, but it keeps much of the information as tribal knowledge and makes it difficult for those without a lot of experience to unequivocally know that "X is an absolute truth". The tribal knowledge can get shared in a forum like this however, and that will help guide more disciplined testing down the road. Growers like @Greengenes707 , @Growmau5, @Scotch089 , @nevergoodenuf , @kmog33 , and so many more here are testing, sharing quantitative numbers (as well as qualitative insights and perspectives) and adding to our knowledge base. Their efforts and generosity in sharing their results will allow us over time to zero in on the most efficient, effective spectrum and intensity. Which I suspect will be a series of ranges rather than absolutes, due to pheno/ strain variances as well as environmental differences such as nute levels, CO2, temperatures, etc.. (Theory. Not fact). And because new tech keeps coming, there will always be plenty of performance trade offs for us to argue about.
BTW, as @JorgeGonzales stated, Amare did put the typical over-the-top marketing spin on it. It would be more truthful for them to say "This light delivers a spectrum and intensity that represents our best understanding of how light interacts with cannabis - given the technology and research available at the moment of final design approval. Opinions may vary". Not nearly as sexy.
I love these discussions for the stimulation but I abhor the snarky, venomous tone. I'd love to be corrected if any of my statements are wrong or disagreed with, but would prefer to not be called a moron in the process. Can't we be a bit gentler? We are supposed to be the enlightened ones...... Or is it that we're supposed to light one? I forget.......
"We truly have far more in common than we have differences".
While true for some posters in this community, I have been doing the speculate, hypothesis, test, and grow cycle for many years, all backed by literature research, practical experience and serious relevant education. I wouldn't draw the conclusion that all posters except for a special few are just speculating without backing and experience.