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)
Great job as usual Maukka, thank’s for measuring the requested mixes :+1:
The thought behind this is to get the tint of a d240 4000K Wizard Pro below the bbl on the medium modes since the current setup is above it even on M3 ~250lm as bob_mcbob measured. And I see 4000K+4500K is slightly below the BBL at around 450lm.
Speaking of, Maukka could you add info about which flux binning you used in cases more than one is available? Eg. your previous the 4000K you measured abut a year or more ago had the d220 bin but now you’ve measured the d240 bin.
I find the results a bit optimistic besides the 5000K (which bin?). At 700mA/led, thus around 990lm it’s pretty obvious the tint is going to be below BBL and the E21A is well known for that. Even the XHP50 WW in the Wizard is below BBL on turbo. 990lm is more a turbo mode than a regular used and sustainable mode in a typical host. What really matters is how every setup performs a medium mode and a low mode which are going te be used by fat the most in real world usage. IMO it would be more interesting to know how they perform at lets say 200lm or even less. That’s where the “big table” helps.
I couldn’t agree more…
But I’m actually open for a positive duv setup for special tasks. For walking in the woods I actually prefer positive duv above a pink tint, maybe because trees aren’t pink and leaves look less green under a pink tint
Or maybe a 4500K (rosy)+5000K(greenish) mix to create a true neutral 4750K…