A couple notes and questions about HDR. For amazon which does not work with the TV app now...has anyone tried an external device over HDMI passing the signal? since ultimately the TV has to do the HDR decoding, I would think the source of the content would not matter unless the external box has some smarts to pass a different HDR signal. Another observation...we recently upgraded Netflix to get 4K. It does detect HDR fine and the interface is SOOOOO much better than Amazon where you need to gather a search party to find the 4K content sometimes. But here is the big negative for me...I believe the HDR processing may take low light scenes and make them even darker as part of the "high contrast effect"...which I assume is all is post processing. For our TV...this brings out the worst as low light scenes can become almost unwatchable...I would be embarrassed to show to my friends. Some content does look good but overall not sure HDR and the way it is processed is a good thing for us.
Try dynamic contrast on low, fixes the dim picture in hdr issue for me.
This "answer" should have gone with this "question".