Why does 1440p look sharp in a 4K display?

[Hi P]

A couple days ago I was watching my cousin play a game at 1440p in a 4k TV, I swear to god we couldn't tell a noticeable difference between that and native.

 

Truth be told, It was a 4K 55" TV standing like 10 ft from us, but our opinion on sharpness didn't change when temporarily looking at it from 5 ft.

 

So I'm confused... why did it look sharp if the 4K TV was displaying 1440p ???

[Monsterkater]

Some TVs do have an internal upscaler, so maybe it was upscaled to 4K? Just a wild guess though

[YoungBlade]

Unless there was some sort of upscaling tech involved, like DLSS or FSR, which can improve sharpness over native images via sharpening filters, it's likely that for that screen at that distance in that lighting with your eye sights, you just can't tell a difference. 1440p is pretty high resolution, and if you're standing 5 feet away from the display, it's not like you're going to be looking at individual pixels.

 

If this chart is accurate, then 1440p at 5 feet from a 55" display is probably the sweet spot to notice the full benefits of 1440p (which isn't specifically listed, but is closer to 4K than to 1080p)

 

[SolarNova]

Also depends on the type of AA the game is using.

'cheap' AA like TAA and FXAA ..blur the entire image. With the right kind of game and setting, that kind of AA can blur the edges of things enough to hide the Aliasing caused by a lower resolution render.  Heavy implementation of DoF can also hide the aliasing found in fine far of details like power lines, and small branches of trees.

Same goes for motion blur.

Disable AA / DoF / Motion blur , and ull likely see a difference.

If not then its probably down to your viewing distance.

 

A lower than native resolution can look perfectly fine when dealing with games, its desktop use with text what is a problem.

[Hi P]

30 minutes ago, SolarNova said:

Also depends on the type of AA the game is using.

The game was Dead Space Remake (2023)

 

I'm not sure if it was the AA or the TV upscaling, but he had set 1440p resolution and it looked sharp.

[Doobeedoo]

Yeah game wise and distance and also possible scaling and AA in use helps.

[Stahlmann]

All TV's have internal upscaling that is far superior than what monitors use. It's the same on my LG C9 OLED. 1440p looks very close to 4K in games because the image is upscaled to 4K, not just streched to fill out the whole screen.

[Hi P]

21 hours ago, Stahlmann said:

All TV's have internal upscaling that is far superior than what monitors use.

Interesting, why is such upscaling not available in monitors?

[Stahlmann]

2 hours ago, Hi P said:

Interesting, why is such upscaling not available in monitors?

In the past it was because of imput lag. But nowadays, a TV can have better upscaling and still have the same low input lag as a monitor. Tbh i don't know why monitors don't have upscaling algorithms built in.