Greetings
I can tell you some things here. XBR Wegas track pretty close to 6500K ... in the range of +/- 100 easily and this is typically from 100 ire to 20 ire.
Non XBR's track not as linearly. Many are +/- 100-200 with the low end spiking to 8000 or 9000K.
Regards
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