Grading HLG/HDR in FCPX (external monitor)
 

I played around tonight with hooking up my Sony X900F HLG/HDR10 4K TV to the HDMI output of my 2015 Macbook Pro. I opened FCPX, pulled up an HLG project, and started messing with settings. Using the TV as an external monitor, I selected OUTPUT RAW HDR VALUES in the preferences, and manually set my TV to HLG mode and BT2020.

Wow, it worked, correct HDR levels and imagery, suitable for proper grading of HDR without needing a separate specialized HDR conversion output box, such as a Black Magic or AJA. I was surprised, as I thought I had read those were the only way to grade in HDR. I also tested an HLG to PQ conversion, and switched the TV to HDR10, and it looked just as good as the final HEVC HDR10 files I have been making.

Feels good to be able to grade and view my HLG/HDR footage right out of this old Macbook Pro's HDMI port. :-)

Re: Grading HLG/HDR in FCPX (external monitor)
 

For testing, I also graded a 720p60 XDCAM EX 35Mbps MPEG2 8 bit 4:2:0 footage shot on a 2010 Sony PMW320, converting it to HDR10. Heh :-D