[Review] E21A R9080 5000K

(*1): LED CCT and tint shifting described clearly in the datasheet provided by Nichia and I also put the link to it in the product page. CCT/tint shifting occurs in any LED, the higher the working current range, the higher the swings. This explains why mid power and COB LED has minimal CCT/tint shift - their current range is limited compared to high power LED. COB and arrayed LED also has less shifting because they have more uniform color separation averaging over angle.
You already have the most tightly binned Nichia: 3 steps and R9080. The higher the CRI the less CCT/tint shifting it will be. Manufacturers always measured the binning CCT at certain current and then provide additional current and temperature shift curve in the data sheet.


To get the most consistent color you better use (lots of) mid power LED (within spec current) or fix the current and use PWM to alter brightness.

(*2): Manufacturers use big calibrated integrating sphere with at least 1 meter diameter. Most of us don’t have such equipment and I consistently put any LED I sell to Maukka since he’s the only person in this community who has the closest equipment and setup to manufacturer’s standard. I’m sure many flashlight manufacturers own such equipment but I have no access to them. LED’s output CCT/tint vary with viewing angle. And E21A is one of the most consistent LED about it.

(*3): could you please kindly take a close-up macro pictures of both LED modules? Your LED was from the same reel and batch tested by the “other” reviewer. I also used this 5000K LED for hundreds of cafe light, streetlight (no optics but PMMA cover), Jet-UE21A, Wizard Pro, and Tiara Pro mods. And I never heard anyone bought those modified lights from me complained about the 5000K E21A horribly colder than expected. So, if you think your LED is defective/different I’m also very curious about it. Just let me know if you’re interested and we can start an investigation openly. I always feel bad when people disappointed with my stuff/service.

(*4): I only provide manufacturer’s data (there’s link in the product page) and add some more missing data not covered in the data sheet which is individual CCT/CRI measurement for each CCT class. So far, I haven’t seen any web store providing this data. I also states each reel binning code, every time I get a new one.

[Clemence]

I don’t think they are defective, and I sure am not saying your store is deceitful. I’m quite happy your store makes these LEDs available to the average person.
But when offering stuff like this to the average person, the listing does need to state anything the average person would not know. Like the fact “CCT ratings are evaluated using integration equipment”. Or that “tint and CCT change significantly with power input”.
One way for a seller to have great customer satisfaction is through great customer service. You do good at this. The other way is to continuously improve the store pages with feedback. You’re store has truthful information from the manufacturer, but in my case, it led me to believe that the CCT and tint were stable properties of the LEDs. I know you did not mean to mislead, but you just made assumptions too, in assuming shoppers already knew CCT and tint were highly variable.

I’m not upset, just disappointed by the general situation that I paid good money and invested good time for a project that didn’t go as expected.

I respectfully disagree with your belief that Clemence is responsible for educating you about how CCT ratings are evaluated, and that he is responsible for educating you that tint changes with power.

And I think you are out of line in your implication that you wasted time and money to do a project that did not work as expected, due to your lack of experience and education with using and measuring LED specs.

I suggest you thank the community for helping you learn what you are doing wrong when attempting to determine CCT and tint values.

That would be like me buying a lathe, and then blaming the manufacturer for not teaching me how to use it.

you bought a tool to measure CCT and Tint, and you used it wrong. Then when people helped you learn the error of your ways, you acted a bit indignant, like you were entitled to an education on how to measure LED properties.

you are not entitled, I suggest you thank everyone for helping you learn why your measurements are not compatible with maukkas

enjoy your lights, and your growing education on how to test LEDs in a way that is consistent with maukkas tests.

Completely agree jon_slider, what Clemence sells are boutique, enthusiast products that require some prior knowledge of how they will be assembled and used.

Basically every single LED on the market has a (usually significant) shift in tint from different angles when run without any optics or reflectors, and when driven hard will often change tint and temp drastically as well (case in point, SST-20 which you have extensively tested).

Couldn’t agree more.
Clemence made countless posts since several years with pictures for tint and CRI comparisons and later send samples to maukka for extensive CRI measurements, some with bare LEDs + with reflector with measurements in the hotspot and spill, etc.
But it’s never too late to learn.

You say you respectfully disagree, but then you go on to straight-up do the opposite. You twist what I said about improving the store into some attack on me. You call me “indignant” when I straight-up said Clemence did nothing wrong or deceitful. My OP was very clear about the how and why I measured the emitter bare. You need to be very careful about stomping on people that post bare-emitter test data, this barking you do creates the situation where BLF has nobody that posts this stuff. You talk education, while barking at test results. These tests were done bare for a good reason, you are in the wrong thread if you can’t tolerate this type of test.

Nobody minds you posting bare LED tests, but claiming Clemence may have shipped you the wrong item or that it’s his responsibility to educate customers about basic characterististics of all high power LEDs is taking it way too far. Clemence provides significantly more information about the LEDs he stocks than literally any other seller in the entire world. He also goes to great lengths to personally assist many customers in selecting the correct product. If you had told him your requirements in advance he would almost certainly have advised you to purchase a different product or take an entirely different approach to your lighting setup design. Nobody is “barking” at you over your tests, they just think you should accept that no one else is to blame here. You didn’t fully understand what you were purchasing or testing, and now you do. Clemence has also very graciously offered to help you investigate further if you believe there is something wrong with the E21As you received.

Where did I claim that?

Again, where did I claim that?

That’s one hell of a claim I think you pulled out of thin air.

Where did I claim I wasn’t to blame?

Again, where did I claim that?

I think there is a different conversation going on inside your head.

Communication is layered and imperfect. The original meaning is rendered into words, transmitted, and then transformed back into a meaning in the recipient’s head. It’s a lossy process requiring interpretation.

People seem to be interpreting certain meanings here, and enough people have done so that it’s probably a fair interpretation. So if the message they’re receiving isn’t the one which was intended, something probably went wrong during the process of converting the original message into words.

Telling the recipients they are wrong doesn’t really solve anything — getting defensive only reinforces the idea that the negative interpretations were accurate. However, rendering the message with clearer words can help. Like, responding with “Oops, that’s not what I meant… lemme go fix that. Thanks!” and updating the review accordingly.

More specifically, I think people are looking for something like this: “I bought these for a specific purpose, but did not know they were designed to be used in a different way, so they don’t work for me. Oops. It turns out that the specs are about the integrated output, not a single-point output. People helped me understand it better though, and maybe with some extra parts I can still use them for what I had in mind since they’re pretty close to spec when used as intended.”

I update the OP with the info from the discussion.

No, it appears what is happening is jon_slider’s single post #16 tried to frame me as if I attacked Clemence, a family member here on BLF. That’s just not what happened, but Bob_McBob was triggered, and took post #16 and tried to evolve it. I trust the edits to the OP are to everyone’s satisfaction.

I know that you believe you understand what you think I said, but I’m not sure you realize that what you heard is not what I meant at all.

Thanks for the updates. It’s not just the OP though. It seems like people’s interpretation of other details is probably fair too, like comment #15. I got the impression that something wasn’t right even before jon’s reply, but didn’t feel the need to say anything because when I scrolled down I found it had already been said. The issues didn’t start when someone pointed them out… Pointing out the issues isn’t the problem.

Going back to the beginning though…

This is defensive and abrasive right from the start, even in the revised version. It frames things as the emitter sucking, rather than being an error in how the emitter was measured. It implies that people in a previous thread were not sane, taking a jab at whatever prior drama inspired this thread. Basically, it starts off with messages which invite fighting and friction, which sets the tone for the rest of the thread. It gives the impression that there is a chip on your shoulder, daring people to knock it off.

Is that an inaccurate interpretation? Was making a contentious point not the goal? If not, set a different tone. Let go of past disagreements and start fresh without letting old battles color the present.


Later on in the thread, things continue and hint that Clemence was at fault somehow, despite going above and beyond what is normal or required for his job. He is typically unusually good about how he runs his business and how he interacts with people, so people aren’t happy about the implication that he did something wrong by only going one extra mile instead of two.

But it is also somewhat understandable to expect more from him, because that’s how human psychology works. If someone consistently delivers 90% of what is required, people will only expect 50% and then be silent when the person doesn’t mess up. But if someone consistently delivers 110, people will expect 150 and then complain when it doesn’t happen. :frowning:

Anyway, with this and some other recent threads, one is left to wonder if the goal is mainly to share useful measurements, or if the goal is more about proving some sort of point.

I hope this makes sense. The measurements are good, and it’s helpful to have more people on BLF doing high-quality spectrometer work. Stuff like that is the lifeblood of BLF. It just seems a bit high in salt, which isn’t good for the blood pressure.

The only remaining rub is how Jon and TK expect me to reverse an unbiased review because they are buddies with the seller. This is not ok.
This is a double standard that you are trying to use to make the Virence review flawless. You would be nothing but thanking me for the review if it was bought from Banggood. Let’s leave the review alone. It’s not fair to be influencing it.

To be fair Joshk, even Toykeeper can make errors. She’s human after all. She’s no perfect.

Back on topic however, did you think about adding a diffusing sheet to the light you are building?

What clemence said is true. CCTs can vary actually vary 10-20% from the spec sheet when viewed directly.

It’s something interesting I encountered during my time at my lighting job.

Powering on 3500k LED strips in a light sphere, I noticed that the CCT was way too high(3950k), unlike I put on the diffusing lens on, where it went down to around 3600k.

I don’t remember the other values, but this is the one which this thread made me remember about.

TLDR: To be honest for once, ToyKeeper is feeding fuel to the fire unknowingly by overcomplicating stuff and trying to understand everybody else’s behaviors. She’s thinking too much for such a little skirmish.

TLDR 2: Specs from the manufacturer were attained during testing.

That is so true. We cannot expect Clemence to write an entire encyclopedia of all possible parameters and scenarios of LED behavior. Even the largest most reputable LED shops don’t provide the in depth information and education on LEDs they sell like Virence.com does. Many veteran BLFers are only recently starting to learn how emitters can produce so different tint depending on how it’s being used. I use to hate the greenish, and high tintshift, LH351D with a passion but now I will be using my M43 LH351D mule for indoor photography and I love the tint when it’s not behind optics or reflectors. I doubt many people realize how nice even a greenish emitter can look when used as a mule as this really isn’t common knowledge yet.

Since even the general LED sellers thousands of times larger than Virence.com and even the LED manufacturers themselves never made any mentions of how their LED can behave so different from spec when used without optics/reflectors or when used with different optics/reflectors/diffusers, I don’t think anyone should fault Clemence for not stating this phenomenon on his website.

Yea I considered putting some of my D-C-Fix in front of the E21, but it doesn’t have a diffusion effect up close, and further away creates a bigger emitting circle. The small point-light was the job of this build. Point lights can create a glisten in the surface reflections of objects. With a larger emitter spot it’s effect is not really different from a typical light bulb.

And I agree it’s a bit out of character for TK to join a skirmish and fuel it.

And yea, in the end the emitter’s behavior has been full explained. And Clemence/Virence is not at fault for what transpired.

You’re taking the encyclopedia idea a bit far, all I suggested was that the Virence store stated something similar to “Posted emitter data was collected inside an integrating sphere, with no optics, and with a power level of 700ma.”

@Joshk, ahhh!

I know what you need!

You need literal light bulb shades glued around the emitters.

Just order some online, or do some dumpster diving and rip apart the LED bulbs.

That’s actually a really good idea! A small frosted piece could do the job up close. I need to find a piece. Thanks :smiley:

I agree. The 700 mAh test seems to be typical for manufacturers to report, but not typical for your max lumens application needs…

Thanks for your time and efforts to acquire tools, take measurements, and share your results.
And Im always happy when variations in measurement protocols, or variations in use patterns, can be found to explain apparent discrepancies in results.

I look forward to more of your contributions.
If anything I say seems offensive, it is unintended.