Originally Posted by jclark2001
I have question for all the Oppo owners. I'm considering buying a UHD player and before I decide I thought I'd ask your opinion on the relative improvement in picture quality over streaming 4K HDR. I currently watch 4K HDR via Netflix, amazon video and was wondering how improvement I would notice from player. As a follow up question, I've only see. HDR10 so can anyone describe relative difference with Dolby Vision. Thanks.
The 4K streams -- with or without HDR -- have additional "compression" applied to them over what you'd get playing from a UHD disc. You just have to look at the relative bit rates to recognize that. UHD discs can play upwards of 100M bits per second transfer rate.
All of the streaming services believe they've done the extra compression cleverly enough that you won't be able to see it, but really, there's no free lunch here. Information is being lost.
For me, the usual tell is in near-black scenes, which show a lot more artifacts when streamed than from disc. The streaming services work under the assumption that MOST viewers won't have their TVs calibrated properly to see dark scenes like that well -- or even at all. So they can play games down there to lower the transmission data rate.
The key difference in Dolby Vision is that the encode can vary the lowest to highest brightness range on a frame by frame basis. HDR10 has to stick with one range for the entire film, which may require some compromises in certain scenes to get them to fit. Dolby Vision is also a 12 bit encode as opposed to 10 bit for HDR 10.
The studios have A LOT MORE practice putting out Dolby Vision encodes for streaming, at this point, than for UHD discs. And there are some signs the tools they've even using for the first disc encodes still need work.
That said, if you play a well authored Dolby Vision transfer from UHD disc -- for example "Transformers: The Last Knight", UHD -- it can look spectacular. (Just ignore the movie itself and concentrate on the eye candy.)
Another problem with Dolby Vision at this point is getting your TV properly calibrated for playing that type of HDMI video. The original scheme for doing that did not work as well as folks hoped, and a new scheme is just in the process of rolling out. This gets rather technical, but suffice it to say that a lot of folks with "calibrated" TVs for other types of content are still using "out of box" settings in the TV when playing Dolby Vision at this point. Which simply means the Dolby Vision, as good as it is today, is still probably NOT as good as the TV is capable of doing once the new adjustment scheme is in place.