CRI test and Mcree weighted results

NoFucks2Give

Well-Known Member
Though in reality 414/477=0,8679
Thank you. My eyesight is not what it used to be. The reason I copy and pasted from the calculator is because I could not make out the numbers very well. I must have missed the ctrl-C key when copying the second number. Still close enough for government work.

It's good to know you are always there checking my math.
I just wish you would do it before the ability to edit or delete times out.
I do agree our realities are quite different.
I am here trying to help. Others are here trolling.
The trolling causes unnecessary posts that clutter and muddles the treads.
 
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sethimus

Well-Known Member
when you measured these cobs like you said you did, are these graphs all showing the cobs at the same wattage or same current like you did last time?
 

NoFucks2Give

Well-Known Member
more relevant to the task than the action spectra you presented so far..
The title to this thread is "CRI test and Mcree weighted results"

I post graphical representations of CRI data and I used the EXACT number from the McCree study, even posted the pages from the study with the values and explained in detail how I used the McCree number to weigh the spectral data posted.

"more relevant to the task" is opinion.
Rather than posting your opinion, why no attempt to explain any specific error you find in scientific methods. Your opinion without rational explanation has no value here.

Please explain how using the McCree in a thread about McCree weighting is less relevant than reflectance and transmittance values from a study regarding the color of cannabis to aid law enforcement in discovering cannabis fields using photography is relative to the action spectrum for photosynthesis.

I hope you realize an action spectrum does not always mean action spectrum for photosynthesis. And an absorption spectrum does not always mean the absorption spectrum of chlorophyll.

If you look at the methods McCree used verses Daughtry and Walthal you will find they are not the same measurements. Daughtry and Walthal differentiated between reflectance and transmittance where McCree measured transmittance and presented it as absorptance. Daughtry and Walthal did not publish absorption spectrum of chlorophyll values nor values for action spectrum for photosynthesis.

___________________________________________________________________________

This may be of interest. Check your knowledge on this topic.
This question comes from this link: http://6e.plantphys.net/study07.html


Explain the concept of quantum yield. Compare and contrast the quantum yields of photochemistry, oxygen evolution, and photosynthetic carbon fixation. Explain the differences between the respective quantum yield values.

Textbook Reference: Key Experiments in Understanding Photosynthesis, pp. 176–178; Organization of Light-Absorbing Antenna Systems, pp. 184–189
 
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NoFucks2Give

Well-Known Member
when you measured these cobs like you said you did
Sounds like you are insinuating I am lying. I have posted the data files used which were recorded using the StellarNet SpectaWiz software.

the cobs at the same wattage or same current
As previously stated the valued used are normalized quantum values. Current and Watts are not relevant.

like you did last time?
What I posted in another thread at another time for another purpose should not be discussed in this thread.
 

wietefras

Well-Known Member
As previously stated the valued used are normalized quantum values. Current and Watts are not relevant.
Normalized to what? What are "quantum" values? Why don't these charts have units and values on the y-axis?

All this uncertainty really renders these charts meaningless to us. It's not "scientific" at all.

Thing is, you describe some calculation which should show "normalizing" but other than calculating some "normalize" constant it doesn't actually do that. The charts don't look "normalized" either, but they seem to show absolute PPFD values per nm. If so, then watts and distance would matter.
 

sethimus

Well-Known Member
i think the stuff he is doing could be usefull if the takes the measurements at the same height and at the same wattage and THEN compaires the ppfd of each cob instead of having them at the same current but different wattage.
 

wietefras

Well-Known Member
Whatever he's measuring can be derived from the datasheets anyway. Rahz already did that at the beginning of this thread and Alesh posted some charts showing absolute power per wavelength too.

Besides, I wouldn't trust anything coming from NF2G, because he compares two COBs while one received 20% more watts. Then cheers it's so much better because it produced a bit more light than the other COB. Yet it was less than 20% more light and one of the COBs was damaged from his poor handling of the COBs. So the whole thing was meaningless anyway. Then who knows at what distance these measurements were compared. We also don't know if he actually mounted the things perfectly aligned with the sensor.

In fact we know for sure he doesn't take any of that into account because he keeps saying/screaming how none of those parameters are important.

How can you trust someone who doesn't even understand the basics to perform these measurements in a correct manner? On top of that comes his incredibly sloppy math.
 

NoFucks2Give

Well-Known Member
Normalized to what? What are "quantum" values? Why don't these charts have units and values on the y-axis?

All this uncertainty really renders these charts meaningless to us. It's not "scientific" at all.
"Uncertainty" as it applies to you. Your uncertainty is unfounded.

My spectrometer is dual calibrated to NIST LED standards for NIST traceable calibrated measurements from 200 to 850 nm. See attached SpectroRadiometerCalibrations.pdf
I use the CR-2 cosine detector.

On top of that comes his incredibly sloppy math.
There is not much math, (just the scaling) involved to warrant "incredibly sloppy math" which does not exist in these charts.

Normalization refers to the creation of scaled values, where the intention is that these normalized values allow the comparison of corresponding normalized values for different datasets in a way that eliminates the effects of certain influences.

In my graphs are all normalized to the CLU028-1204C4-303M2K1where it is scaled as explained in a previous post with all the math.
Where is the incredibly sloppy math???
I convert the $spectra from text to decimal $values.
$max = max($values);
$scale = 280/$max;
$normalize = 1/$max;
for each wavelength I get the x and y values to be plotted
$y = round(300 - ($scale * $values[$wavelength] ));}
$x = ($wavelength - 380) * 2;
Then add the vertical line for that wavelength to the SVG image.
echo '<line x1="' . $x . '" y1="300" x2="' . $x . '" y2="' . $y . '" stroke="#' . $hex[$wavelength] . '" opacity="1"/>' . "\n";
Here is where the scale was set for the chart which is 280 pixel in height: $scale = 280/$max;
In this case the scale is 81x and this scale was used for all the charts in these posts.
This scale is based on the CLU028-1204C4-303M2K1 peak value of 3.4076E+000 @ 614nm which if added to the chart would be meaning less. If you really wanted to know this value you could have looked it up in the measured data attached to the post in document:

What are "quantum" values?
Quantum: see attaced ConversionLux.pdf

The term quantum comes from the Latin ‘quantus’ for ‘how much’ as in amount or quantity. A quantum is considered to be ‘a discrete packet’ with energy stored in them. For example, a photon is a single quantum of light.

From Merrium-Webster: any of the small subdivisions of a quantized physical magnitude.

In LED lighting Radiometric values refer to the energy in the photons measured in watts. Photometric and Luminous are the radiometric values adjusted to the sensitivity of the human eye. And Quantum is the quantity of photons independent of the amount of energy carried by each photon.

Why don't these charts have units and values on the y-axis?
The purpose of normalized charts is to remove superfluous information that tends to distract.

the graphs are simply a scaled values for a visualized comparison and units would only be a distraction. Although I did mention the values before they were scaled and I did included the files with all the data used. I did not feel the units were necessary for a visual comparison. I fail to see how these numbers on the horizontals would be of any value for the purpose here, but if you want you can add them yourself. Knock yourself out.
Untitled.jpg

Thing is, you describe some calculation which should show "normalizing" but other than calculating some "normalize" constant it doesn't actually do that. The charts don't look "normalized" either, but they seem to show absolute PPFD values per nm. If so, then watts and distance would matter.
The reason they appear to show absolute PPFD values is becasue they are scaled from absolute PPFD values as stated in my post:
3000K 80 CRI 484/477 µmol/m²/s
2700K 97CRI 430/414 µmol/m²/s
What matters is not the distance or watts, only that the distance and current were the same. The distance is shown in the photo.
watts/m² also are irrelevant see ConversionLux.pdf

Distance and watts only matter for the graph titled "3000K 80 CRI minus 2700K 97CRI" comparison to be accurate when the difference was graphed. That is why I stated this:

Each CoB was measured at the same distance from the detector and driven with the exact same Mean Well HDD-H driver with a fixed current.
In normalized charts the actual values do not matter. It is a comparison. It only matters that the SAME distance and current were used. I use the exact same LDD-700H driver.

For purposes of comparing the spectra of the two LEDs to to CRI (first post) distance and wattage would not matter at all (even if they were different) and both LEDs could have been normalized to their own max values as is done in SPD charts in the datasheets.


Whatever he's measuring can be derived from the datasheets anyway
The data I measured cannot be derived from the datasheets unless quantum flux intensity is given. You can estimate the radiometric Flux Density with the SPD chart. You cannot derive mol/m²/s (flux intensity) from lux or W/m² or mol/m².

If the datasheet includes Intensity (W/sr lm/sr) you could make an approximation of of radiance W/m²/sr or luminance (lm/m²/sr) becasue they both have steradian in the denominator. .

If you were to read (and understand) my post you would know exactly what was measured and exactly what is displayed on the graphs.

Rahz already did that at the beginning of this thread
I did not see the color graphical representations of the PPFD and the difference between two CoBs.
I do not believe there was any spectral comparison of each wavelength to show the influence of the particular wavelengths as they are related to CRI.

Alesh posted some charts showing absolute power per wavelength too.
Alesh does not have PPFD values. His values are estimated PPF. My values are actual measured PPFD with an instrument where the calibration is traceable to NIST standards using a cosine detector.

RECAP

The only math needed was to scale the measured values to fit on a chart with a height of 280 pixels. All numbers were multiplied by 81.
Distance and watts did not matter, only that they were the same for both sets of measurements.
The measured values cannot be calculated from the datasheet as there is no conversion between measurement geometries, for example, W/² and µmol/m²/s or PPF (µmol/m²) and PPFD
 

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NoFucks2Give

Well-Known Member
i think the stuff he is doing could be usefull if the takes the measurements at the same height and at the same wattage and THEN compaires the ppfd of each cob instead of having them at the same current but different wattage.
You must have missed this if you read the post.

Each CoB was measured at the same distance from the detector and driven with the exact same Mean Well HDD-H driver with a fixed current.
Both CoBs were CLU028-1204C4 both having a forward voltage of 34.6V.
The same fixed current driver was used.

I could find the height and current in my records if it were necessary, but it is not. I spent a considerable amount of time on this post without including irrelevant data. The distance is in the picture. The current was either 350mA or more likely 700mA. But it does not matter which.
 

sethimus

Well-Known Member
You must have missed this if you read the post.



Both CoBs were CLU028-1204C4 both having a forward voltage of 34.6V.
The same fixed current driver was used.

I could find the height and current in my records if it were necessary, but it is not. I spent a considerable amount of time on this post without including irrelevant data. The distance is in the picture. The current was either 350mA or more likely 700mA. But it does not matter which.
the decor and the luxeon cob both have different voltages, they are the only cobs im interested in. so compairing them with different wattages is something i cant get my brain behind. can you elaborate why that shouldn't be an issue when you compairing ppfd which is usually higher if the cob gets more power then the other?
 

NoFucks2Give

Well-Known Member
they are the only cobs im interested in.
The post in this thread compares two CLU028-1204C4 CoBs.

I understand why you and your fellow trolling CoB Snob Bully @wietefras, want to bring in anther post into this thread to support your trolling. I suggest you go to that post and reply with any comments. Comments regarding that post do not belong on this thread.

Beware that @wietefras completely misinterpreted what I was doing in the Vero Decor post. I was asked by another member to test the Vero at 700mA. The purpose of the equations at issue in that post was to verify the measured spectral ratio of lux to PPFD. They were NOT used to compare PPFD per Watt as @wietefras incorrectly assumed. It was @wietefras that use the damaged CoB in his equations to incorrectly compare Watt/PPFD using the incorrect PAR value and measured with a damaged CoB. Although since that post I compared the damaged CoB to another one I have and even though damaged the PAR output is the same. Lumiled use a load balancing circuit in this CoB becasue they have parallel strings. When one string dies the current is split between the remaining stings keeping the flux at approximately the same level.

If you look at the attached document you can create a factor to convert between measurement geometries. I was making the spectral power distribution measurements to create that conversion factor. All I needed at that point is the relative PPFD intensity at each wavelength. Distance and wattage did not matter for those measurements as long as both the lux and PPFD measurements were made at the same wall watts. The conversion factor applies to only one LED so there was no need to use the same wall watts for two different LEDs. If any comparisons were to b e made between the two LEDs it was better to keep the current the same rqather introduce more error by changing the current when the inverse square law could be used to convert the spectral power distribution to whatever level was required. @wietefras also errored back then when he said distance did not work in that instance becasue the inverse square law was about changing the distribution of the measured area.

@wietefras also incorrectly assumed the CoB was damaged by being mishandled. I use CoBs for thermal experiments and they do get damaged due to excessive heat. Considering that CoB melted the solder on the contacts 3 times, it still works very well. The forward voltage is a volt higher than the spec'd max level. I explained this to @wietefras previously but he insists on incorrectly stating it was mishandled because of the troll he is.

Yes there were some typos, I finished the post after 5:00 am and after drinking a 12 pack of Bud. Unfortunately I could not delete or edit the post the next day.




.
 

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NoFucks2Give

Well-Known Member
the decor and the luxeon cob both have different voltages,
I have dozens of measurement files for both the Vero Decor and Luxeon Red Meat. I am not very inclined to assist you when you and your buddy @wietefras, troll me.

I do not believe you have interest in these two CoBs. It is very possible you are just trying to drag up a conflict between me and your CoB Snob buddy, @wietefra, in a previous post a few weeks ago. Why else would both of you bring up that post?

I have PPFD, Radiometric Watts, Lux, various heights, and wall watts. I can create whatever someone desires. The two CLU028-1204C4 CoBs used here I purchased, out of pocket, to run some tests for another member, a non-trolling member.

I have two Luxeon Red Meat CoBs. I accidentally used the damaged one, but seeing it did not matter for measuring spectrum, I did not bother to redo the measurements with the good one. Then the next day I was going to redo them to compare and found the two generated almost identical PPFD flux.
 
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VegasWinner

Well-Known Member
I have dozens of measurement files for both the Vero Decor and Luxeon Red Meat. I am not very inclined to assist you when you and your buddy @wietefras, troll me.

I do not believe you have interest in these two CoBs. It is very possible you are just trying to drag up a conflict between me and your CoB Snob buddy, @wietefra, in a previous post a few weeks ago. Why else would both of you bring up that post?

I have PPFD, Radiometric Watts, Lux, various heights, and wall watts. I can create whatever someone desires. The two CLU028-1204C4 CoBs used here I purchased, out of pocket, to run some tests for another member, a non-trolling member.

I have two Luxeon Red Meat CoBs. I accidentally used the damaged one, but seeing it did not matter for measuring spectrum, I did not bother to redo the measurements with the good one. Then the next day I was going to redo them to compare and found the two generated almost identical PPFD flux.
I would ,like to get your advice on a board I am developing with two channels 1-3500k and 1-5000k utilizing 192 samsung lm561c diodes each channel for a toal of 384 diodes at 50w per channel 100w power board. Here is a link to the thread ->https://www.rollitup.org/t/diy-4x12-3500k-5000k-lm561c-two-channel-board.944214/
sorry for interrupting your thread, but I could not get your attention any other way. thank-you and please continue explaining your views. I rather enjoy them
namaste
 

NoFucks2Give

Well-Known Member
@wietefras you are a perplexing individual.

As far as the green hole syndrome (green window), there is not a scientific consensus on the topic
Your response to the above post you want to be seen as an expert on relative quantum efficiency which you so casually (and incorrectly) refered to as "McCree RQE"[sic]. When technically McCree used the term relative quantum yield of photosynthesis where just the term quantum yield could refer also to quantum yields of photochemistry, oxygen evolution, and photosynthetic carbon fixation. But I digress on that topic.

Bullshit.

Where do you think the definition of PAR comes from? It's a simplifcation[sic] of the McCree RQE. Why do you think they use YPF to be even more accurate than PPF?


Seriously, stop it already.
I then replied with "Engelmann is turning in his grave" This is where PAR began in 1882:

Engelmanns photosynthetic action spectrum.jpg

I like how the little buggers go to blue and red just like the action spectrum of photosynthesis.

And in 1882 the green hole/ window begins.

Maybe use this chart to weigh the quantum spectrum of LEDs instead of McCree. We can digitize this curve. Scientific consensus still holds Engelmann to be valid today.

Fig. 1 came from this page: http://photobiology.info/Gorton.html

_____________________________________________________________________________________________


Then later on in an unrelated post I said:

As previously stated the valued used are normalized quantum values. Current and Watts are not relevant.
Then lo and behold, you are no longer and expert on quantum yield (or as you said McCree RQE[sic]).
When Quantum Yield is all about quantum and quanta, you now do not know what a quantum value is when the other day you were an expert on quantum.

Normalized to what? What are "quantum" values? Why don't these charts have units and values on the y-axis?
On one hand I do not like you muddling these threads with your trolling, on the other I hope it is educational enough for other to learn and that cancels out the negatives of your trolling as I correct you.

Here is where this gets interesting for everybody. The following book reference does a good job of simplifying the terms action spectrum of photosynthesis, action spectrum of O2 Evolution, and quantum yield of photosynthesis.

Refer to the attached document Chapter 11. In a paper written by Heliospectra in support of white LEDs for photosynthesis the paper suggested Chapter 9 of the book where this Chapter 11 comes from.

On page 143 the book describes "action spectra". Then towards the bottom of the page it says "absorbed quanta per second is the quantum yield"

Yet you are an expert on "McCree RQE"[sic] but do not know what a quantum or quanta value is. How is that?

Page 144 describes more about action spectrum of photosynthesis using the term quantum and quanta over and over again segueing into Emerson and Maximum Quantum Yield.

Then on page 148 begins the section titled "THE MAXIMUM QUANTUM YIELD OF PHOTOSYNTHESIS". Which starts off with moving from Relative QY to absolute QY then goes on to say:

We shall now say something about the absolute value of the maximum quantum yield, or minimum quantum requirement of photosynthesis.

Then down on page 150 it gets into how the quanta of photons utilized, "2 quanta for the transfer of each hydrogen atom from H2O to CO2" and the "8-10 quanta per O2 molecule".

This book was probably written before or around the the time of the McCree paper.






.
 

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NoFucks2Give

Well-Known Member
i was just asking questions.
Insinuating I faked my measurements did not help. Echoing @wietefra did not help.

Okay, I apologize if you were being sincere. I have been trolled by @wietefra for weeks now, liking his post did not help either.

Whatever measurements you want from the Luxeon Red Meat and or Vero Decor 1750 CRI97 just let me know. I will deliver ASAP

If you want to send me a CoB with a return self addressed stamped envelope to return it to you. I will measure it for you too.
 
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wietefras

Well-Known Member
On one hand I do not like you muddling these threads with your trolling, on the other I hope it is educational enough for other to learn and that cancels out the negatives of your trolling as I correct you.
Pfft stop deluding yourself. The only posts people are learning something from is our posts correcting your bullshit. But then that is all so basic, the people who have been here for more than a few weeks would know this already.

Not that it's helping much for you, you keep barfing over this forum as if nothing happened. At least you are slowly getting some understanding of McCree and the difference between PPFD and PPF. Of course now you pretend you invented the whole McCree chart to begin with :roll:

Anyway, we weren't talking about your personal take on McCree. Nobody cares about that nonsense. We were talking about the rainbow colored charts you keep spamming over all threads you posted in. Like I said, they are useless if you don't put some minimal needed information on them to indicate what they are supposed to mean. They need units and numbers on the Y-axis too. Not only nm on the x-axis. Also when you say they are normalized when they are clearly not, is also rather off putting.

Although of course the fact that you have no clue what are doing sort of ruins them anyway. Like you not understanding that watts, angles, distance and proper handling of tested devices matter when comparing PPFD measurements. You are comparing completely incomparable measurements.
 

wietefras

Well-Known Member
Indeed, but his goal was to make it "not relative" (I'm not allowed to say absolute), because relative SPD's are already in the datasheet. But now he claims it's "normalized" and therefore watts, distance etc don't matter.

But then "normalized" in NF2G's made up jargon just means that it's capped at some random maximum value. So of course the charts are really absolute umol/s/m2 per nm charts with data from the spectrometer. Which means that of course watts, distance etc DO matter. As we have explained dozens of times now.

It's amazing how hard it is for even simple things like this to sink in. I thought at some point he did realize you cannot compare PPFD measurements of a 50W COB to a 40W one. It took at least a week to get that point across. Yet now he just spams the same charts and same false conclusions again. *sigh*
 
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