agree, the 4500K 519a runs low, I just tested one of mine at 4200K, duv –0.0005
the nominal CCT that an LED is binned at is not exact, LEDs vary, in this case by 7%.
imo metered values vary due how bright the light is when tested, in addition to differences in the LEDs from one to the other, plus differences between the instruments used to do the test.
Even LEDs from the same roll, side by side neighbors, can have these variations.
Next up is my measurement of Convoy S21D with Nichia 519a 4500k shows 2 interesting findings:
CCT is ~4100k, not 4500k.
Duv is negative, versus the positive number that Simon got using his Hopoocolor meter.
I was surprised by the negative number, considering the beam color looks more yellow/slight greenish than magenta if compared back to back with 219b, so I posed the question on the lightmaster thread Opple Light Master III (G3) discussion thread (Cheap device for measuring Lux, CCT + CRI) - #392 by cannga and found other people seem to be getting negative numbers also. No big deal since variations are expected.
Simon’s specs for 519a 4500k: Ra 93.6, R9 82, R12 80, Duv 0.00091
(Not bad at all. Check out R9 ——> 82. In other words this is also a R9080 led.)
My 519a 4500k measurements with Opple Lightmaster Pro (trial runs), in Convoy S21D with Sofirn Clear Optic (the OEM frosted optic’s numbers didn’t change much):
100% Brightness: Ra 97.3, Duv –0.0037
20% Brightness: Ra 97.6, Duv –0.0018, range: –0.0020 to –0.0030
Agreed. I should emphasize the only time I see any greenish tint in 519a 4500k is during back to back comparison with 219b 4500k or 3500k. By itself, it’s a beautiful golden light.
Jon, very good points to keep in mind (comparison more valid when not compared across different test devices, brightness, LED batch, etc.). That way we could stay relaxed and have fun while learning something.
I’m sure you’ve noticed there are 3 zero’s in front of Simon’s value. So his number hugs the BBL very close, maybe not a “huge” difference from my 20% brightness value. ie Simon’s ~ .001 (round up from the seemingly large 0.0009) versus my .002, and your.000.
Yes there is something about a small light that fits completely in your palm with side switch. It feels right/very good. And D4V2 is very pretty.
I couldn’t decide between Hank’s and Simon’s lights so I got both.
:confounded:
If you do get Emisar D4V2, I would add a couple comments: I do NOT like the option of raised ring around button (takes away from the smooth feel), and if you get brass or copper option, they are extremely pretty, but also very heavy.
Out of curiosity, what does this mean in layman’s terms? I already have the 12A version, so I’m wondering what changes if you get the 8A. Differences in output or runtime?
The 8A version is more efficient, and is this likely to result in higher sustained brightness, and longer, but not quite as bright turbo.
I’ve just ordered the 8A CC 60 degree 519A 5700k version.