A double-blind study carried out by Pixar, Amazon, LG, ASC and Warner Bros found that few viewers can tell see the difference between 8K and 4K content on an 88-inch 8K OLED TVs, according to a report by Techhive.
4K TVs versus 8K TVs
Multiple TV makers have started selling 8K TVs but there has not been much research into the benefits of 8K TVs. FlatpanelsHD has also found that some of the early 8K TVs are not capable of reproducing 8K resolution and last year we advised our readers not to buy an 8K TV of any type.
A comprehensive, double-blind study carried out by Pixar, Amazon, LG, American Society of Cinematographers (ASC), and Warner Bros - and described in impressive detail by Techhive - has now examined the subject, with the goal of finding out if viewers can see a difference between 4K and 8K.
For the double-blind study seven different native 8K HDR10 video clips (see box on the rightabove) were shown on an 88-inch 8K OLED TV (LG 88Z9) to 139 participants over three days. Participants were seated in two rows at about five and nine feet from the screen, respectively. The 4K clips were downscaled from the 8K clips and then upscaled again to 8K on a PC using four-pixel duplication (cubic).
- "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. 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 (see Fig. 3). In the third sequence, the 4K version was played four times, though the participants still saw the labels “A” and “B” alternate and scored them as before. This provided a control group to assure more robust statistics," Techhive explained and added that "each participant was evaluated for their visual acuity".
Since it was a comprehensive study that also took into account the viewers' visual acuity, for example 20/20 vision or 20/10 vision, results were presented in several different ways.
- "In the average of all results, the 8K clips were rated 'marginally slightly better' than the 4K clips," said Techhive.
When evaluating only results from viewers with better 20/10 vision, two 8K clips (A Bug's Life and the nature footage) were rated "slightly better" than the 4K clips.
Lastly, all "slightly better", "better" and "much better" responses were combined into a single "better" score to account for the nuance that people may have different perspectives on what is, for example, "slightly better" as opposed to "better". The outcome was these two graphs.
Left: Distribution of scores - Right: 3 grades of "better" combined into single score
As you can see, many viewers rated the 4K version higher than the 8K version, which obviously should not happen.
- "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. 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," said Michael Zink, VP of Technology, Warner Bros.
We recommend that you read the full article on Techhive.