Thor: The Dark World arrives on the UHD format with a standard configuration 2160p/HDR encode. The UHD is certainly sharper and cleaner, more glossy and crisp than the Blu-ray. Facial elements are appreciably more revealing, showcasing Odin's facial hair and scars with greater attention to detail and intimate clarity. Tactile environmental details around Asgard shine, while costumes are amazingly intricate in close-up, particularly considering Thor's and Heimdal's. The image is richly defined and very clear. It's superior to the Blu-ray, perhaps not by leaps and bounds but the UHD improves upon the digital source which per IMDB was photographed at resolutions of 2.8K and 5K and finished at 2K. Of the five films released in this August MCU UHD wave, this is texturally the best looking of them and, not coincidentally, the least processed looking, the least to stray too far from its source, similar to Iron Man 3.
The HDR color spectrum renders the movie far darker than the Blu-ray. Even without making the direct comparison it's obvious just how dim and shadowy the movie appears, and that feeling is only amplified when studying various shots and scenes back-to-back. Compare a scene early on, about five minutes in, when Loki, in chains, appears before Odin on the throne. The UHD is notably less bright, rendering the scene looking almost as if it's taking place at dusk whereas the Blu-ray has the look of well-lit daytime, even as the scene plays indoors with light streaming in from windows around the room. Shadows are more dense, too, and it's more of a challenge to examine the writing on the collar around Loki's neck or see the texture on Loki's clothing. But it's at least a natural look beyond some of the extreme examples, and the greater color depth and density are revelatory, such as seen on Thor's red cape and metallic gray armor which are amongst the standouts. Various bright light sources -- lightning, weapons fire, the light bridge, and so on -- enjoy a fairly substantial boost to depth and boldness. Skin tones are pleasantly natural as well. It's a fairly radical departure from the Blu-ray, not in terms of any aggressive wholesale changes to core colors in any given scene but rather the major add to depth and push to a far deeper end of the spectrum.
The included Dolby Atmos soundtrack begins inauspiciously. It's active but a bit flat to open; action effects and Odin's narration are somewhat volume-challenged at reference settings. It does otherwise enjoy plenty of surround usage and some engaging dynamics that see various elements zip and zoom through the stage, promising characteristics that the track does build upon afterwards. Though to open the track lacks superior low end response and greater volume to action elements, things do pick up beginning with the battle on Vanaheim that fares a bit better than the first, offering even greater surround engagement and a fair amount of bass to effects and music alike. The track does hit a stride where a fairly strong, though not substantial, low end supports various effects. By mid-film, action proves surprisingly tight and rich, certainly not to the greatest standards but well surpassing the usually puny Disney presentations. For stage spread, top end integration, low end engagement, musical might, and atmospherics, everything appears in very good working order. Dialogue is firm in its front-center position. It is well prioritized and naturally detailed throughout, with only slight shallowness as noted in those opening minutes.
4K Bluray detailsVideo
Codec: HEVC / H.265
Resolution: Upscaled 4K (2160p)
Aspect ratio: 2.40:1
Original aspect ratio: 2.39:1
English: Dolby TrueHD 7.1 (48kHz, 24-bit)
French (Canada): Dolby Digital 5.1
French: Dolby Digital Plus 7.1
German: Dolby Digital Plus 7.1
4K Ultra HD
Two-disc set (1 BD-66, 1 BD-50)
Movies Anywhere, iTunes, Vudu, Google Play
Slipcover in original pressing
4K Blu-ray: Region free
2K Blu-ray: Region free