Thanks for the impressive reply!
I tend to agree with you, iTunes doesn't offer the quality of a true 1080P Blu-ray Player video image, being internet compression leads to banding in dark/bright color in od dark space scenes etc, (Darn, I absolutely hate that) to a far greater extend than on Blu-ray Players, in fact, that doesn't occur at all on a Bly-ray Player.
My TWC cable is set to Component being the HDMI is 1080i, and very pixelated. I rather sacrifice the 1080i to a full scan in 720P, which turns out to be deeper in color, not as many blurred pixelated motion scenes.
My internet connection is 100 Megabytes down, and 25 Megabytes up, plenty of bandwidth for one person, alone in a household. My Wi-Fi streams sometimes on an iPhone in a test at 120 Megs down... So all the 3 media streaming devices are receiving their fair share of broadband, most than many households.
Do you ever think, from an Apple standpoint, this will ever be resolved using a supposed internet compressional 1080P video stream to be comparable to a real Blu-ray experience? I also have the new Sony BDP S6700 with Triluminos (2015-16 Model). There are those out there who disagree with Sony's claims, but I do notice the life like colors, of course on a Sony TV, maybe its in my head!
But even in a streaming app, such as Netflix (I cannot access iTunes on that device, but if I did, I think it would do better than the ATV4), the color space is quite stunning, more vivid, deep, with true flesh tones.
My opinion, there are just too many options out there now, experimenting, whereas iTunes has been around for much longer. So I do tend to buy Movies in iTunes, more than the other services, although iTunes doesn't offer the ability to sync with Ultra Violet, which is obvious. I don't know where it will all lead to, but I am betting on the internet as being the sole source of TV entertainment within the next 10 years... Cable is still dishing out 1080i, such a joke!
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I do have a myriad of settings on my HDMIs, terms I'm not too sure about, and maybe you can help me with this...
I have 5 HDMI inputs, 3 components, 3 composites (I don't use those anymore) and 3 Videos (really have no idea why they are there) and 3 PC types, DVI, VGA, and mini display ports (You can configure a USB Type C -1)
Here are some of the options on the separate HDMI settings:
Color Matrix - selection of "Auto" or all the resolutions, including 1080P with ITU709, or ITU601.
I don't know the difference between ITU601 or ITU709
RGB Dynamic Range - selection of "Auto" or "Full" or "Limited" - I left them all on Auto
Photo Color Space - selection of "Adobe RGB", or "sRGB" or "sYCC" - they are all on "sYCC"
Video Color Space - selection of "x.v.Color" or "Normal" or "Auto" - these are all set on "x.v.Color"
CineMotion - selection of "Auto" or "Off"
Then there are Text, Gaming, and Photo selections which doesn't apply, way too many options.
Sony doesn't have, anywhere in the manuals, what these will do, but I am assuming on the Video Color Space, the settings for x.v.Color is basically for another Sony device, such as a Sony Blu-ray Player, syncing true color with the HDMI inputs. Sony has the 1080p/24 which is basically the way the picture was made in Cinema Film.
Here is my take on as many services I use:
iTunes - steady, never any buffering, no color banding in dark to light, overall near 1080P but not quite.
(for me, no buffering ever occurs on any devices, yet, with that kind of bandwidth)
Vudu - HDX, steady, never any buffering, some color banding, however more brighter and wider color range using Roku 4.
Amazon - Okay, close to 1080P but more muffled, blending of colors, high compressional methods for 4K, noticeable but nice job.
Netflix - the best service I have seen, both using the ATV4, Roku 4, and Sony BDP S6700, a bit true like Blu-ray on the Sony.
Hulu - quality is near Netflix, but still notice, not much, color banding on all devices.
HBO Go - I bring this up because it has a quality server, picture is overall near 1080P on all devices, but they left out the "AUTO-PLAY feature on the ATV 4, and Roku 4 which was and has been very disappointing, I have tried over and over again to contact the developers of that app for especially the ATV 4, but to no avail, they figure you can air-play it from your iPhone, but they do not realize, if you air play it to the ATV 4, you still cannot autoplay, you still have to hit a few buttons on the iPhone for the episodes to continue, being the iPhone, even wen mirroring it to the ATV 4, goes into lock screen mode, and looses that ability to autoplay... How sad :-(
Thanks so much, I hope this offers where I am standing as far as video streaming over the internet. Best