The higher pixel count afforded by Ultra HD TV (also known as 4K) alone might not be the best way to entice consumers to move to a new generation of television.
That was the consensus of the pros in attendance at a recent symposium of the Society of Motion Picture and Television Engineers.
As 4K — including the continued effort of Netflix to experiment with 4K content delivery — has recently been in the news, it seems like an appropriate time to re-examine the topic.
Here’s the basics of the issue: Digital pictures are made up of building blocks called “pixels,” and to improve a picture, the industry can address a few parameters. First, it can add more pixels (known as resolution), for instance with 4K, which represents four times the number of pixels found in today’s HD.
It can also offer faster pixels (higher frame rates), which addresses image artifacts such as motion blur. The public became keenly aware of this option in large part due to Peter Jackson’s use of higher frame rates when he made and released The Hobbit: An Unexpected Journey.
The group referred to the third variable as “better” pixels, involving a higher luminance range (brighter and darker pixels) and wider color gamut (more colorful pixels).
At the conclusion of the SMPTE symposium, the general consensus seemed to be that it was a combination of these improvements that will have the most value.
But what if they could choose only one? By a show of hands, the majority of the hundreds of engineers in attendance voted for better pixels, with a fair amount choosing faster pixels (higher frame rates), leaving 4K a distant third with just a few supporters in the room.
Offering one viewpoint on the topic, Dolby Laboratories recently conducted some research in this area, which the company’s executive director of technology strategy Pat Griffis shared with The Hollywood Reporter.
According to Griffis, the research concluded that if the industry focuses only on resolution it is “ignoring opportunities” afforded by the other parameters to “increase the palette to tell stories, as well as create a better representation of reality for news.”
According to Dolby’s findings, “better” pixels in particular can result in a a greater perceived improvement, while higher resolution (“more” pixels) is less noticeable and only at close distance.
Griffis therefore asserted that striving for more pixels alone might be moving to the point of “diminishing returns,” particularly when you add viewing distance to the equation. “Yes, you can see [a difference] with more pixels, but only when you are close up,” he said. “Brighter pictures you can see from across the room, so ‘better’ pixels may well be the low hanging fruit to consumer-perceived value.”
The study of “better” pixels involved examining the wider range that the human eye can perceive. Using “nits” (a measurement of light sources), Griffis related that direct sunlight can reach 1.6 billion nits while starlight can be 0.0001 nits.
He pointed out that while it’s unlikely that any single image will vary that dramatically, a still outdoor image (see the above example), might include direct sunlight that could produce 300,000 nits on a car, while a shadow might only reach 15 nits. “In the real world we can see these at the same time,” Griffis said, adding that this is not the case with today’s television sets.
According to the exec, today’s displays have a far more limited range that only reaches approximately 100-120 nits for the brightest white, while cinema caps at just 48 nits (14 FootLamberts) for the brightest white. “That is one of the problems we have in representing the real world. That is like looking trough the world through a peephole,” Griffis asserted, adding however that that industry is in a time of change with a “new generation of displays that are capable of much higher performance and getting much closer to representing what the human eye can see.“
What is a useful range for entertainment? Dolby’s research concludes that creation of a future TV standard that ranges from 0. 005-20,000 nits can be the ideal—and is an achievable goal. “That is 200 times brighter than where we are today,” Griffis said.
“As we look to the next generation of image formats, it the view of Dolby … that we ought to design for the human eye and what would be representative of the real world.”
THR’s Behind the Screen blog will continue to examine the varying perspectives on this topic.