A majority of viewers are unable to discern the difference between content shot at 4K and 8K resolutions, according to a new study that concludes the higher pixel density doesn’t really offer any advantage.
Critics of 8K TVs have long held that there’s a limit to the resolution that humans are able to perceive on video screens at a normal seating distance. But exactly where that limit is, is not clear. Nor is it clear if 8K displays offer any kind of benefit to viewers. And so to settle the question once and for all, Warner Bros., Pixar, Amazon Prime Video, LG, and the American Society of Cinematographers teamed up on a double-blind study to see if a random assortment of viewers were able to tell the difference between 4K and 8K content.
The study involved showing an audience of 139 participants a selection of seven different video clips shot in native 8K HDR10. The participants were seated in rows, five feet and nine feet from the screen, and shown the clips in a random order. The 4K clips were downscaled from the 8K footage.
“In each session, the 4K and 8K versions of each clip were played in three sequences, though the sequences for each clip were not presented one immediately after another,” Techhive reported. “In two of the sequences, the 4K and 8K versions were randomly assigned the labels “A” and “B” and played twice in an alternating manner—that is, A-B-A-B—after which the participants indicated which one looked better on a scoring form.”
The third sequence tried to trick the audience by playing the 4K version four times and not showing any 8K content at all, though it still used the “A” and “B” labels. This was done to provide a control group to ensure more robust statistics, Techhive said.
Participants were also evaluated for their “visual acuity”, for example if they have perfect 20/20 vision or just 20/10 vision.
The full results of the study show that the 8K clips were rated “marginally slightly better” than the 4K versions.
However, the results show that many viewers actually rated the 4K clips as being “better” than the 8K content, which is not supposed to happen. At least not if believe the claims of 8K's superiority made by companies like Samsung or LG.
“I believe the reason you see a large number of people rating 4K better than 8K is that they really can’t see a difference and are simply guessing, said Michael Zink, vice president of technology at Warner Bros. “The more interesting point is the fact that for all clips except Clip 7, most people scored “4K the same as 8K”. And “8K better than 4K” is second most scored option. For Clip 7, it’s different, and most people scored “8K better than 4K”, which was an interesting take-away.”
