I feel like I am missing something very obvious here, but I've been hitting my head off this wall for a little while now. I have the Zidoo Z9x, and I've been very happy with it, it's hooked up to my old Optoma HD25 HD projector, which while getting on a bit, has been a trooper. Problem is, some movies (most recent was Rogue One) have a very noticeable blue shift in the picture, for example the rings that pan across the screen in the introduction are very obviously blue, when I play it from the Apple TV, hooked up to the same display they are grey. It's always dark scenes, but it makes some flesh tones and the like look very, very odd, they almost jump out of the screen, and it's very disconcerting. Again, same content from the Apple TV plays fine. I assumed it was something weird with the HDR-SDR conversion, but I have tried most settings in there, with little difference. I thought I'd fixed it by forcing the VS10 engine, but now it looks off again! I am using the recommended settings that were posted in here, but have obviously changed a bunch to try things as well. Has anyone else seen anything similar, or can anyone recommend something else to try? Thanks!
I've currently got it on Dolby Vision VS10 engine (globally effective) but I do feel like I've tried most settings there! I thought it was HDR related, as it definitely seemed worse with UHD content, but now I'm less sure!
Ok - I thought you were going to say "Highest Rec.709" since that uses the Realtek engine to do the SDR conversion and that definitely results in chroma issues in blue because the Rec 709 > Rec 2020 conversion is pretty bad. But the VS10 engine is very good at HDR > SDR and colour mapping (definitely better in the newer models though) and doesn't result in a blue shift at all so I'm not sure what's going on there. With the Apple TV are you using online or local content - ie are you using the same file for comparison?
On the Apple TV I am using Disney+ as the version of Rogue One on the Zidoo is a Blu-ray ISO which sadly I can't test on the Apple TV. I can try and get hold of a version that I can play on both for easier comparison though. Strange you mention the Rec 709, as that was what it was on when I originally noticed the issue, which I then seemed to fix when I switched to VS10, when it cropped up again, it had changed back to Auto, so I assumed changing it back to VS10 would fix it, but it didn't seem to make any difference. Maybe I need to factory reset...
Ok that makes sense - the ATV will serve a native Rec709 version rather than convert internally - that's how streaming services work - they have separate encodes for SDR, HDR10(+) and Dolby Vision and will serve the version to match the output selected in the player - in your case SDR Rec709 due to the EDID. So you'll probably always see some difference between a streamed version and a local version. Also the streamed versions are re-encoded by the streaming service provider to match their low bandwidth requirements so they are heavily compressed. You could try a factory reset - always worth a go when behaviour is unecpected.
