Sony 'mastered in 4K' Blu-rays a mixed blessing

The "mastered in 4K" name is sure to confuse many buyers this year, but Sony's special new Blu-rays are an impressive boost in quality over your average Blu-ray release.

Seamus Byrne Editor, Australia & Asia
Seamus Byrne is CNET's Editor for Australia and Asia. At other times he'll be found messing with apps, watching TV, building LEGO, and rolling dice. Preferably all at the same time.
Seamus Byrne
4 min read

The "mastered in 4K" name is sure to confuse many buyers this year, but Sony's special new Blu-rays are an impressive boost in quality over your average Blu-ray release.

You'd be excused for thinking this Blu-ray is in 4K. It isn't, but it is still very good. (Credit: Sony Pictures Home Entertainment)

Sony is pushing its status as the only company able to deliver a complete 4K experience "from the lens to the living room". As part of this business integration — from movie studios shooting and finishing films in 4K through to new 4K televisions hitting the market in coming weeks — Sony is eager to deliver something that gives viewers a reason for choosing Sony ahead of Samsung, LG or another company.

Enter Sony's "mastered in 4K" Blu-ray releases, which will hit the market around the same time as Sony 4K televisions (we will find out Australian availability later this month). These films are specially mastered to deliver enhanced quality over standard HD movies, particularly when viewed on a 4K TV.

That statement alone encourages consumers to make some bad assumptions. No, these discs are not 4K; they are still HD Blu-ray discs. Sony representatives have been using phrases like "near 4K", but we are still talking about movies delivered in 1920x1080 that will be upscaled to 3840x2160.

When discussing these new "mastered in 4K" discs with technical staff at Sony Pictures, there was a clear disdain for using 4K terminology on discs that are not 4K. Confusion may breed resentment, and ultimately cause a negative reaction to the value that real 4K content will deliver once the content is ready to be delivered in its truest form.

On the other hand, "mastered in 4K" Blu-rays also turn out to be the best picture quality ever produced on a Blu-ray disc, and will really look amazing when played on a Sony 4K TV.

There are three technical measures that elevate a "mastered in 4K" disc above the rest:

  1. Enhanced bitrate: these discs exclude content extras in favour of using all available disc space to deliver the film in a greatly enhanced bitrate. Where most Blu-ray discs are typically delivered in rates in the 24Mbps to 30Mbps ballpark, these "mastered in 4K" discs deliver at 35Mbps to 38Mbps. A greater bitrate means a much clearer picture, and less moments where blocking or blurring will occur, particularly in action sequences.

  2. XvYCC support: in the Blu-ray standard, xvYCC (also known as x.v.Color) is a colour space option that to date, has almost never been supported. XvYCC extends the available colour gamut to better represent the colour space that the original film was intended to be displayed at, while the standard sRGB space cuts off a lot of information in the red and blue-green sections of the spectrum. As long as your Blu-ray player and your TV support xvYCC, these discs will deliver a solid colour enhancement over other discs on the market.

  3. Sony 4K algorithms: this final feature is a sweetener focused on giving Sony 4K TV owners a better experience with these discs than any other 4K TV owners. Being part of the same family, Sony Pictures and Sony Bravia have shared proprietary algorithm information to give the best possible upscaling performance on these films. Sony 4K televisions will be able to identify a "mastered in 4K" disc and use an upscaling algorithm based on the same formula used at Sony Pictures to downscale the film from 4K to HD. This secret sauce is likely to give a Sony TV the edge over other TVs that must use less-specific algorithms to upscale the content.

Viewing a "mastered in 4K" disc side by side with the same footage displayed in true 4K video, you have to be looking very carefully to pick up on the difference. But that leads to another dilemma: is Sony's stop gap "mastered in 4K" going to create another scenario where 4K TV owners don't see the benefit in buying true 4K content? Could HD Blu-ray be "good enough" in the same way that DVD has mostly been seen as good enough for HDTV owners?

These special edition discs are undoubtedly little more than a stop gap until a final 4K Blu-ray format hits the market, and spending money on a movie collection that will be outdated next year also seems to be a dud play. But they do give an enhanced experience, so it isn't just a marketing exercise.

The best-case scenario would see these movies offered up as a bundle deal with the purchase of a new Sony 4K TV. Then they move from the awkward (if gifted) step-child to a sweetener that gives great value today while you wait for perfection tomorrow.

Fifteen films are scheduled to be released in the format, ranging from recent releases like The Amazing Spider-Man, Total Recall, The Other Guys and Battle: Los Angeles all the way to classic films restored in 4K, such as Lawrence of Arabia, Taxi Driver and Ghostbusters.

Seamus Byrne attended a 4K television press event as a guest of Sony Australia.