This is really cool, and I should definitely try some E21A emitters.
Any idea how a 2700K+6500K or 3000K+6500K combo would look? Ideally I’d hope to hit near 4200K with duv –0.008 or so.
Edit: On second thought, perhaps I should just go for the 4500K emitters by themselves. They seem just about right, aside from being a bit less rosy than desired. With the flat surface, it’d probably have a fantastic beam.
Open the chart in a photo editing program and draw a line between the emitters you’d like to mix and eyeball the xy coordinates at the middle point. Enter them to a calculator such as this one: Calculate Duv from CIE 1931 xy coordinates | Waveform Lighting
edit: as it happens, in my image the duv (with a bit of a multiplier) is pretty much the 1:1 pixel distance from the BBL, so that helps too
Amber looks like a low CRI extremely warm LED. Mixing red and amber can produce something interesting…I request a test for this Maukka.
Red on the other hand is very close to Cree’s new 660nm XPE2 photo red except it has very wide spectrum coverage. A very good candidate for night vision friendly torch.
Thanks Maukka for providing those extremely useful test data for us. I have a few questions.
1) Why does tint mixing drop R9 so much on the 2000k+ 6500k
2) Could the low R values for 2200k be a fluke?
3) If I remember correctly the batch of E21A you tested last year was much rosier. Is that correct? This batch seems to hug the BBL similar to the Optisolis.
Also a request if it doesnt require too much effort is if you can test 2000k+2700k, 2000k+4000k, and 2000k+4500k. Of it require much effort to setup the test then nevermind.
Let me try to answer those.
2000K has quantitatively more red than 6500K. 6500K measured with D65 standard while 2000K with incandescent baseline. Combined, the resultant R9 will result in less R9.
Early test done at 100mA current. Some LED produces less CRI at low current, and more R9. Different behaviour for different phosphor chemistries.
2000K and 2200K rated at R9050 not R9080.
Thanks for making that measurement. I suspected it would end up being unbalanced. Trying to build anything around this mix would result in a freakshow light if current to each channel can’t be managed separately. One the other hand, being able to adjust each channel individually would be what would make an RGBA light fun.
It seems like blue would need to be dialed back quite a bit, and perhaps the amber increased a little in order to get a more natural result.
GREAT job Maukka . These integrated measurements is extremely close to OEM rated, a good example of what to expect from 3 steps binned Nichias. Many thanks for all your efforts.
FYI, this also closer match to my tint shots in the OP (no optics, matte white reflector)