What puzzles me: I can set the color temperature via the UI and the light also changes, I can switch on and off, etc.
Once I switch the light off and on via the color ruler again, the color temperature is again in UNDEF.
Is that behavior on purpose or am I doing something wrong?
The color temperature of a lamp corresponds to a co-ordinate that lies on the “Planckian Locus” in the CIE Color XY color space. And if a lamp has a color co-ordinate that does not lie on this locus then its color temperature is indeed undefined.
When you command a lamp via its Color Temperature channel then it will go to a point on the Planckian locus. But as a general rule (unless you are quite lucky, or very accurate) if you command a lamp via its Color channel it will go to a co-ordinate that is NOT on the Planckian locus
Ah I understand.
So the behavior is totally okay.
Thank you very much. I know the image you added, but never got the clue that I might run in an undef…