Here's a generic chart of screen size vs viewing distances, and whether your eyeballs will be able to discern a difference between normal 1080 HD or 4K (Ultra HD).
So, get out your tape-measure and see how far away your couch is from your TV. If you have a 60" screen, and sit 7' or more away, you will not see a discernable difference in clarity. If you have a 70" or larger screen, you can be 9' or more from the TV, and you'll see a difference.
Charts like these are based upon human eye resolution; and it's only with the larger TV sets that you get any real advantage from the higher resolution.
Most people are 6'-8' or further from their TVs. Which means 4K only becomes significantly clearer for 50" to 65" or larger TVs.
Answer (1 of 8): There are a few articles on internet (reputed sites like C-Net, Tom’s Guide, THX, etc.) that explain. They have charts too. I have picked up a couple of charts to explain: Source: Broadcast | Production | NAB | Broadband | Satellite | Mobile | www.tvtechnology.com In the above ...
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