This issue has been brought up many times in the past, and for some users this issue still exists, even in DaVinci Resolve 16 beta2.
The problem is that the GUI viewer LUT selection does not work in edit and fairlight.
The GUI viewer LUT selection does work as intended for color and deliver.
With version 16 the CUT page is added, and this page too, does not work at all with the GUI LUT selection.
Rather than go over everything again (system specs etc....), here are links to older and more recent threads :
https://forum.blackmagicdesign.com/viewtopic.php?f=21&t=74894https://forum.blackmagicdesign.com/viewtopic.php?f=21&t=91503To re-iterate, when selecting an external monitor LUT, this incorrectly gets applied to the cut, edit and fairlight viewers as well, even when the viewer LUT is set to 'no lut'.
Only selecting a LUT for the viewer LUT (and no external video LUT) does not work at all in cut, edit and fairlight.
Everything works as expected in color and deliver.