Synology + HDR Content

[TheDreadPirate]

This is where my first question comes into play, if I uploaded HDR content to Jellyfin and play it on an HDR compatible device like an iPad does it do any transcoding? While watching on the iPad is nice, I plan to do most of my movie viewing on a Windows computer. This computer has an RTX 4080 and an OLED ultrawide from Dell so HDR should be fully supported. (I know it is when playing games).

Your Jellyfin server will only transcode when the client tells it to.  It is possible that the client incorrectly determines it can't play something directly and asks for a transcode.  Or the other way around.  It can't play something and doesn't ask for a transcode when it should.

The actual HDR data is separate from the video.  So if your client mistakenly determines it can play HDR but actually can't it will still play but with washed out colors.  It is very obvious.  When I play HDR content on my not HDR Windows 10 PC monitor it is not transcoding or tone mapping and the video looks normal.   So you saying that you couldn't tell might indicate that your iPad is processing the video correctly?