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По умолчанию Color Rendition and Tint Comparison: Cree, Rebel, GDP, Nichia

There is always a lot of discussion here on the relative color rendition quality of various LED emitter types (and the specific color temperature/tints within those models). I typically like sticking with objective test data that I can measure in a reliable way, but I thought I would try my hand at doing a relative subjective comparison between emitters and tints.

It is very hard to capture subjective visual impressions with a camera, but I've come up with the following method to try and facilitate the presentation:
  • For samples, I have picked lights with what I consider representative tints and emitters. Most of these are not specific known tint bins, but are based on my relative visual impressions compared to other lights in my collection (see Addendum for my tint bin estimates).
  • I've chosen as my test objects common colorful items a flashaholic may have on hand (including various common battery types, typical office supplies, and a few other familiar items .
  • Since the lights all differ in beam profiles, I've chosen to do a ceiling bounce comparison in a closet with white walls and ceiling, with my camera mounted on flexible portable tripod.
  • I've picked lights that can operate at relatively similar outputs, and equalized the exact output as close as possible on my camera (Canon Powershot S5). Specifically, I've set the white balance to daylight, locked the aperture at f2.7, and varied the shutter speed to capture equivalent overall exposures using my camera's built-in histogram feature (I manually set the shutter speed to generate as close to a perfectly centered histogram as possible for each light, thus equalizing the overall exposure).
  • For more details on the actual lights used, and my estimate of tint bin, see the Addendum at the end of this post
Click on the individual pics to bring up full-sized images - works best if your browser supports multiple tabs, so that you can easily switch between tabs and see the pics in a stationary way.















Again, click on the individual pics to bring up full-sized images.

Combination Comparisons:

To help you compare tints at a glance, below is an animated gif showing one "representative" tint for each of the four emitter types. Note the total colors had to be reduced to 256 for the GIF format, so you will see some hatching. I also had to reduce the overall dimensions, to keep the final file size down.

Animated GIF of the four emitter types:


I will leave it to you to draw your own conclusions about relative CRI (color rendition index) of the various emitters in this test.

To be perfectly honest, personally I don't find that there's a huge difference among the various emitter samples. I think a lot of it really comes down to tint differences (which are great enough to obscure subjective color impressions). To help show you what I mean, here are the 6 Cree tints shown in an animated gif.

Animated Gif of the six Cree tint samples (from cool to warm):


I don't know about you, but I find the reds and browns show up a bit better on the "warmer" tint Crees. The cooler tint Crees tend to look "whiter", and are better for distinguishing the blue and blacks. The differences within an emitter class thus seem greater to me than between these emitter brands.

Bottom Line :

Note that I am not making any claims as to the scientific validity of my testing method above - I'm just trying to find a way to easily compare lights at a common overall exposure and removing any beam pattern effects. The specific settings of your graphics card and monitor will make a huge difference in how these images appear. Also note that the "daylight" white balance setting can be highly variable from one camera to the next, which would skew the results. So there are many possible confounds here - this is just meant to be an approximate comparison.

But at the end of the day, I don't really see a noticeable color rendition difference between any of these particular emitters. Subjectively, I am far more influenced by relative color tint and temperature differences, and I think there would have to be a pretty significant CRI difference for me to really notice it in use. Of course, I hope that will change as newer LED emitters come out with significantly improved CRIs (e.g. I haven't tested the new Seoul "natural white" 4000K yet, or the new K2s). But since all the emitters here typically have a CRI >70 (with incans being ~100 CRI), I am not really expecting huge subjective improvements. But YMMV, and I welcome any observations you might have on the pics above.

Personally, I would just go with whatever tint and beam pattern you most prefer for a given task. For example, I personally like a premium to slightly warm "cool white" LED for general use. Outdoors, I like the slightly warm "cool white" tints for greens/browns - but don't like going as far as the "neutral white" Cree 5A tints. And my wife likes her cool tint Fenix L2T V2 Rebel - she uses it every morning to help her pick out matching black socks in her sock drawer (trust me, you can't do that with my warm-tinted lights).

Hope you found the pics useful!

UPDATE: In case you are curious about the terms used here, please check out the CPF Welcome Mat for general background on tint and color temperature, among a great many other things.

------------------

UPDATE: although I didn't do outdoor shots for this comparison, I have previously compared the Cree neutral-white Fenix TK20 (likely 5A tint bin) to the standard Cree cool-white Fenix L2D (likely WD tint bin) here:




------------------

Addendum:

In case you are curious, here are the actual lights I used, with my estimate of the tint bin:

Crees (from top to bottom above):
  • Zebralight H50 (cool white, cool bluish tint - I'd estimate WA/WB bin)
  • JetBeam Jet-I PRO IBS (cool white, cool purplish tint - I'd estimate WM bin)
  • Nitecore Defender Infinity (cool white, very premium white tint - I'd estimate WC bin)
  • Fenix L1D (cool white, warm yellowish tint - I'd estimate WD/WG bin)
  • Olight M20 (cool white, very warm yellow-greenish tint - confirmed WH bin)
  • Fenix TK20 (neutral white, likely 5A bin)
Rebels:
  • Fenix L1T V2 (cool white RB080, cool bluish tint - I'd estimate Y0 bin)
  • Fenix L1D (cool white RB100, warm yellowish tint - I'd estimate VN/UN bin)
GDP:
  • Nitecore D10 (cool white, overall yellowish tint but slight bluish corona)
Nichia:
  • AltusLumen PAD-L (cool white 0.5W, new emitters with premium white with slightly warm yellowish tint)

For help understanding the tint bin codes, CPF user DFiorentino has compiled graphs for many of the major emitters here.
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