The highest colour space/chroma my Philips 4K TV will handle is 4.2.0, as advised to me by the Philips engineers (I assume they should know what they are talking about). It is showing on the information that it is playing from a UHD 4K disc at 2160p/24fps. It does not display the colour space. So that via the HDMI handshake, even if the Samsung is capable of sending 4.4.4, it is not doing so, as that could not be read by my TV and it cannot downgrade the chroma internally, so it must be the K8500 that is doing so. Even if I change manually to 4.4.4 colour on K8500, the info on the TV does not change and it carries on playing as before with no noticeable effect on the appearance, so presumably the Samsung is (very sensibly) ignoring my instruction due to the handshake via the HDMI.