(cont'd from first posting) ...
Now the weird thing, I don't understand:
I set the 3D Video Monitor LUT for correcting the Video-Monitor at the Decklink-Card:

- Settings_LUT_SetOnVideoMonitor.jpg (132.01 KiB) Viewed 2037 times
That's the only change i did.
But now the scopes also show the color off.
You can see, the grey is no more stright grey, but it's going to red:

- Scopes_LUT_SetOnVideoMonitor.jpg (170.3 KiB) Viewed 2037 times
Also the GUI-Preview is affected from the Video-Monitor LUT:

- Preview_LUT_SetOnVideoMonitor.jpg (36.23 KiB) Viewed 2037 times
As far as I understand, the 3D Video Monitor LUT in the project settings should only correct the output via Decklink to the video-monitor so the video-monitor shows grey, where the clip is grey and the scopes show gey.
It should correct the video-monitor to match the monitor to the scopes and the clip-pic-data.
But with the behavior of resolve shown above, the correction will never match the scopes.
In addition, it will cause to do a wrong color-correction because the Video-Monitor LUT will mislead the colorist while looking at the scopes.
With this behavior IMHO it's not only useless but it's dangerous to set Video Monitor LUT.
I don't understand:
Is it a bug or a feature?
Or do I have to set any other settings to get the correct behavior of Resolve?
Thanks for your help.
Peter
Resolve 12.5.4 Studio