Originally Posted by BillyClyde1115
You said all UHD BD players, but then said you wanted to get a Sony to try out. Have you tested the Sonys too. Can you clarify?
I have not tested the Sony UHD BD player for basic image quality properties like:
1. Image cropping
2. Chroma alignment
3. Chroma upsampling quality.
4. I need to measure the player using the monotonicity pattern (YCbCr) with an HDMI Analyzer to know if it correctly reproduces all values from 4-1019 in Y, Cb and Cr.
Number 3 is subjective. Luma (Y) is 3840x2160 for UHD. Chroma (Cb and Cr) is 1920x1080 in 4:2:0 for UHD. Chroma is 1920x2160 in 4:2:2 for UHD. And chroma is 3840x2160 in 4:4:4 for UHD. Chroma upsampling is really chroma scaling. How good is the scaling? Does it ring when it scales it up? Is it sharp or soft? Many players use bilinear, which is softer but does not ring. OPPO appears to use something like bilinear. Panasonic UB9000 uses something sharper and has some ringing. This is no different than resizing an image using bilinear vs. Lanczos other than its difficult to discern chroma issues on normal content, which is why they can get away with 4:2:0. You look for the same type of differences. It is usually a comprise of sharpness vs. ringing. There are some pretty great chroma upsampling algorithms that people have written on Windows. To be clear, not stock Windows and the built-in media players don't use them. 3rd parties like MadVR and others.
This is where the chroma resolution patterns come in handy. If you use a WFM, you can see how well the player does. If you look at them on a display, you don't know if it is the player, display or both causing quality loss. LG has a true 4:4:4 mode, which shows the best chroma I have seen on a display. Sadly, in 4:4:4 mode, bit-depth drops and banding is painfully obvious. On the quantization rotate pattern, the 10-bit bottom looks just like the 8-bit top. In the normal mode, 10-bit is much smoother. The Z9D has some pretty bad chroma roll-off. If you look at the chroma zone plate, the center third is noticeably brighter than the left or right side thirds. Center is the lowest frequency and it goes higher towards the edge. When it gets dimmer, that detail is rolling off or being filtered out. On the LG in 4:4:4 mode, its equally bright across the entire image, hence my comment about it being the best I have seen. In normal mode, it is dimmer on the outer thirds, but still brighter than the Z9D. Keep in mind, the source material is 4:2:0, so scaling up and down (4:2:0 -> 4:4:4 -> 4:2:2 -> 4:4:4) may degrade the image. And some may filter on purpose based on their subjective opinion.
If you look at the chroma of Panasonic vs. OPPO into the LG when it is in 4:4:4 mode, you can see Panasonic is brighter towards the edges than OPPO. That means more chroma detail. Will you see this in real world material? If anything, possibly animation like Pixar. The test pattern is designed to make the most subtle difference stand out.
You can see examples of this in our Choosing a Color Space article
using the Color Space Evaluation pattern.
Brighter is not always better. Nearest Neighbor will be the brightest, but will be out of alignment. (YC delay)