I was just wondering if anyone here has ever tested to see if using optics like the common 3x carclo type deteriorates CRI? The main reason I ask is I’ve been using some of the 90 CRI optisolis emitters in a tripple and noticed a very nasty shift in color when using them. It turns my 5000k color temp into like 6500.
With a wide optic the color is smooth and even just cooler than it should be. With a narrow optic I get three blue dots surrounded by some varous warmer colors. When I mule it the beam us not a great pattern but the color is about what you’d expect. A nice white with a mild tan overlay.
The Optisolis is special and does not work with smooth optics. Most single-die LEDs should work in clear optics if they fit. The current Cree LEDs will produce an ugly green corona or spot, just like with smo reflectors.
The optics don’t reduce CRI. They may have some effect on tint just like AR lenses. Tint shift is another matter altogether and just like The_Driver said, Optisolis needs a diffuse optic to prevent that nasty shift. Otherwise the hotspot is very cool, while the edges turn yellowish green and warm.
I didn’t happen to have a frosted Carclo 10623/10624, but I sanded a Carclo 10622 and while the results were good, the edges of the beam still had visibly warmer temperature to them. After adding d-c-fix the beam turned perfect. Add a mild minus green for that rosy goodness.
Thank you guys for the input.
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Maukka, just to make sure I understand correctly. The test your showing says 4974k temp, that is with the optic in place correct? So I assume this is the 5000k temp rated version of the LED and your saying proper diffusion will eliminate the tint shift all together?
So I finally got to try the Oslon Square 2700k 96CRI 6U tint bin and 3500k 92CRI 5Q tint bin. The 2700k is the nicest warm white tint I have ever seen and R9 is even higher than the E21A and SST-20 95CRI when I shine it on my wood texture table. For reference, I have tried a number of warm white emitters, Cree XM-L2 90CRI, XM-L2 7A 70CRI, XP-E HEW 7A2 90CRI, XP-G2 HE 90CRI S2 7A1, XP-L2 V4 7A 70CRI, SST-20 95CRI HD2, Nichia 219B 9050, Nichia E21A 3000k, Yuji, and a few others. The only one I haven’t tried yet is the 219B 9080 3000k but I already have some that I will try in the future. But until then, the Oslon Square 96CRI 2700k is the BEST warm white I’ve ever seen.
The 3500k 92CRI 5Q tint bin looks great too and possibly the best 3500k tint in existence unless compared with the mixed CCT emitters. My Tiara Pro from Clemence with quad E21A 2x 3000k with 2x 4000k still looks the best for 3500k. But it’s hard to beat mixed CCT especially if the E21A tint was so good to begin with. R9 of the 92CRI Oslon is noticeably not as good as the 96CRI Oslon. It is also worst than the SST-20 95CRI and E21A. Even the 219B 3000k 9050 has better R9 than the Oslon 3500k. But that is not to say it is bad. Color rendering and R9 seems to edge the 219C 4000k 90CRI by a bit.
Cree is claiming to have added 95 CRI value to XPL2 and XHP50.2 (in their newsletter). I would like to see how these stack up.
A clip from the news letter:
New! TLCI 90 & 95 Options Added to XP-L2 & XHP50.2
If you develop sport or entertainment-focused lighting products you no longer need to choose between illumination optimization for eyes or cameras. You can have them both with Cree’s enhancements to our leading high power products. These new 5700K CCT options give you.
Best possible illumination for eyes and cameras
Reduced energy utilization for optimal illumination for broadcast videography
TLCI 90 and 95 ratings ensure minimal video-chain color processing and compensation for broadcast video.
Interesting, but I find myself somewhat hesitating. Until now high CRI Cree led emitters have been found less desirable versus others concerning rendering quality and tint, hope that is to change and get better. I used this opportunity to read about TLCI:
