This is weird. I’ve tested many E21A (photo comparisons etc…) and have been using them until today, none deviates that much from those in the data sheet. And many people also satisfied with them. To my eyes, 5000K and 5700K are two CCTs most resemble daylight. Only 6500K appears “too blue”. I said this not because I sell these LEDs, but E21A is very popular for reasons.
In my opinion, your profile picture looks way too cool if they’re 5000K E21A. Too warm WB perhaps? You can check my beam and tint shots for comparison.
I’ve used probably 7-8 different reels of sw45k and they’ve measured anywhere from 4200K-4700K in a reflector, so I wouldn’t read into that too much. Plus bare LEDs, integrated LEDs, optics, and reflectors will all produce different results.
I trust what you are saying Clemence. But something is definitely up. Could there have been a mixup with some higher CCT ones in the same drawer when they were built, or just a different bin/batch?
BTW, both my quads perform same.
As for the profile pic, I believe the camera was set to 5000K as it should have been, but I can’t be sure anymore.
Forgot Joshk tested the LED at max 2A. That’s beyond the 1400mA limit for E21A. So, that’s normal. Maukka tested the LED according to Nichia’s binning current at 700mA.
With and without optic or reflector makes a very big difference in both CCT and tint. Here are two examples with the SST-20 4000K. Bare emitter is always much cooler.
Like the current, and the angle at which you measure the bare led. A diffuser like dcfix will average it somewhat but will still only catch and diffuse less than half of the light. Moreover, a any diffusor causes loss of blue light and warms the tint because of blue scattering more than the other wavelengths. Using optics selects other parts of the light again.
The only way to measure average tint is with an integrating sphere coupled to a spectrometer. It integrates the full 180 degrees of output and the sphere can be characterised by measuring the colour-specific light loss over the spectrum and correct for that. Maukka is the only amateur I know of to have that setup and post results with it.