Has anyone else tried the 92cri version? I'm really digging it. I just ordered some more.
I did 
haven’t really have the opportunity to try them, but so far I like the tint…different than 219A, but still nice.
I have, obviously, and as stated in the OP, I like it a lot as well. Going to make a triple with it, I hope this week, with a Convoy S5 as a host.
So is there a verdict on the Kaidomain 219Bs? I see they’re still for sale.
Are they for real?
Offering both 1mm and 1.5mm bases
http://www.kaidomain.com/product/details.S022878 etc.
I still have no verdict, they have a good tint and I can not measure CRI. Only thing that I or someone else could do is get the 219b that intl-outdoor is selling (there"s no reason to distrust them), build two flashlights and compare the tints directly (and even then it is not easy I guess). But it is not in my planning.
I used the KD 219Bs in a triple Solarforce Z1/BLF-17DD, and compared to the almost certain genuine real 219Bs from IlluminationSupply in a Roche F6 triple/F6DD I can't find any difference, in output or tint.
Thanks for the info comfy!
One word of warning on making comparisons, especially the tint: drive them too hard and they will shift to the very cool side. Not quite full-on blue like direct driving a XML on aluminum, but the tint shift between 'high' and the next lowest mode is easy to spot if you look for it. Output will fall rapidly from the initial level too if you check it with a luxmeter.
It happens instantly, too quick for it to be blamed on the MCPCB or anything farther down the thermal chain, it's the LED package/substrate causing it. Switching down one mode makes the tint go instantly back to normal, and switching back up to high instantly makes it go cool white again.
The F6/triple is fine even with a 25R or VTC5, but there's only one cell. The 4x SRK is the one that turns blue but only after I braided the tail springs. It works fine with low drain cells now, but not with INRs. And swapping spring plates to one that's not braided makes it work with the 25Rs again without issue.
Has no one noticed that the R9 of these new emitters is is big fat “0” and nichia doesn’t release R10-R15 numbers? The “9050” version of the new emitters is supposed to have an R9 of 50 but no one as of yet is selling this version. These days I expect to see manufacturers release R1-R15 numbers for their “high CRI” LED’s… Only seems to happen with COB’s aimed at interior lighting though.
Would you explain that in more detail?
The Wikipedia article explains how eight color samples [R1-R8] are employed to calculate the general color rendering index Ra. The article shows the whole range of the color swatches [R1-R15] and talks of better and different standards as well.
CRI and its shortcomings are explained as well on the SHARP website.
Sharp, Xicato, Bridgelux, Soraa, and Yuji are examples of companies talking about and listing R9-R15 scores for their high cri emitters.
As for the new Nichia emitters, the high cri ones show R9 listed as >0, which means better than 0. There is a “9050” version however which is 90+ CRI and with a R9 of 50, which should render red much better. I suppose for us flashlight folk it comes down to tint and the perception of light quality which, you know, what more could you want than a tint that you like and seemingly decent reproduction of colors? I have been getting into indoor lighting for a while though and I guess my tint snobbery has started to cross over. Somebody stop me!
Thanks. Still reading. So far the things that seem to make the best tests of color rendering are flowers. Some flowers are deep red, as I see when they are lighted with a Philips Luxeon deep red led.
Somewhere I saw spectra of various leds, but I failed to find them again later. Clearly flat or very smooth spectra are good for most purposes. I read here somewhere the suggestion that brighter than normal color may be desirable for some purposes. It seems that could be achieved by a spectrum that had peaks near the centers of the human primary colors (presuming that those can be identified in some approximate way). Clearly bright reds should be rendered as bright reds, so your criticism seems founded.
The main feature of white led spectra is the blue spikes. I have been looking for things with colors that miss the blue spikes by being more violet or more greenish, shorter or longer wavelength. It seems that the colors of those things should be noticeably distorted, perhaps looking more like the color of the blue spike, but I haven’t found a good example.
I have not even been able to see the difference between the Nichia and Cree leds, other than the appearance of the white itself.
It may have been links I posted where you saw spectra, if that helps.
a few more or less randomly that might help:
http://i.imgur.com/SB8opNy.png
http://ledmuseum.home.att.net/specx31.htm
http://www.1023world.net/diy/spectra/ (lots!) (much in Japanese I can’t read.)
I really like this emitter even if it doesn't attain 92 CRI. It has a very nice tint and the CRI seems really good to me. I especially like that it has comparable output to an XPG2 R5 up to 3 amps while having slightly lower Vf. I think that if it is proven that the KD emitter is 92CRI, it will no longer be 5 for $13.xx.
sshhht, keep it quiet!!
I just realized I spoke of 2 different emitters in the above post. The xpg2 comparison was the 5500 temp emitter, not the "92" CRI emitter.
The emitter is definitely promising, for sure, and I will probably use it over XP-G2’s in the future, I just thought the R9 was disappointing on the 92 CRI version is all.
What about using color histograms to compare color rendering of objects under various lighting sources? So, you take a control shot under daylight, or an incandescent light or other true high CRI source. Then, you use some software to come up with a histogram from that photo. Then, you take another shot with the exact same camera settings with the light source being tested, such as a Nichia 219B from KD. Compare histograms to see where the CRI is lacking in your test subject. If you want to compare two LED’s to each other, you do the same thing. This way, camera settings and eye sensitivity or human tint preference wouldn’t matter. It would be pure data. It would not actually tell what the CRI value is or should be. Although, with a chart of known CRI values to compare to, you could “calibrate” your equipment such to get really close. It would be most useful for comparing two sources to each other. It could also be used to evaluate one’s tint preference. Compare the histogram of a photo taken as illuminated by your favorite LED to a histogram of the same shot taken in natural daylight with the same camera settings to see how your preferred tint differs from natural light.
What ruins it to some extend is the primitive rgb-detection of the camera, it does not detect wavelengths directly. A bit more sophisticated way is use a spectrometer, like the simple and cheap, but effective one that bigmac_79 used in his Imalent review. Real CRI can not be derived from those spectra either because the values are not direct photometric power values (but pixel values of the camera whatever they represent), but you can do the trick of dividing two spectra you want to compare, so you get rid of the absolute values and just see the difference relative to each other.