If the ATV is outputting 4K SDR/30hz then by definition you're not getting an HDR signal. The HC4040 should report the incoming signal specs via remote's info menu.I finally got my screen setup and I think I figured out how to get my Apple TV 4K to play nice with my refurbished Epson 4040. I have the Apple TV 4K set to output 4K SDR 30HZ, which is the highest refresh rate for HDR that the projector supports. Putting my output settings to 4K SDR 30HZ took the projector from getting no signal to getting what I believe to be 4K with HDR, however, I'm hoping there is some way that I can verify in the projector that it's really getting 4K and HDR. Any tips?
Additionally, if I was to try and copy some recommended settings for this projector, would I be better served using settings/calibration from an Epson 5040 or an Epson 4000?