4K scaling question

[Easy Rhino]

How well do 4K monitors scale down?

For instance, I doubt I will play any games at 4K (for now) but would like to play at 2K.

 

[SQr]

How well do 4K monitors scale down?

For instance, I doubt I will play any games at 4K (for now) but would like to play at 2K.

Gaming at 2k looks good enough, just loses a bit of the sharpness. 1080p looks blurry. I have the Samsung U28D590D monitor.

Tried both monitor and VGA scaler, both look identical.

 

[newtekie1]

In my experience 1080p looks sharp and clean on a 4k monitor. Of course that makes sense considering every 1080p pixel scales perfectly to 4 pixels on a 4k monitor. So the pixels are just 4 times as big.

 

[Vego]

I also have a U28D550 Samsung and I like the picture more in 2560x1440 over 1920x1080. It looks like AA effect. The 1080p just enlarges pixels four times and I don't like it.
Also I highly recommend you to pick IPS monitor over TN. I'm selling mine and buying IPS.

 

[newtekie1]

It looks like AA effect.

That effect is the blurring from the pixels not aligning properly. IMO, if you want AA, turn on AA.

 

[SQr]

In my experience 1080p looks sharp and clean on a 4k monitor. Of course that makes sense considering every 1080p pixel scales perfectly to 4 pixels on a 4k monitor. So the pixels are just 4 times as big.

I wish it did do 1:4 scaling, which it doesn't. The monitor uses some silly interpolation to upscale the image instead, which makes it really blurry @1080p. That's why both the monitor and my 290x scaling look the same, as they use similar upscaling.

 

[GhostRyder]

How well do 4K monitors scale down?

For instance, I doubt I will play any games at 4K (for now) but would like to play at 2K.

Eh, personally when I tried it the machine looked similar to my 1080p monitor sitting next to it that is similar in size. I though it was ok, I tried 1440p and it seemed great as well but I did not try a game or something at that level (I tried a 1080p game once on the 4K monitor but that's it).

I would say its fine for that, but that is just my personal opinion.

 

[ShredBird]

Depends on the scaler in your monitor. Things that evenly divide in general will look better (1080p), but if the scaler is cheap it can look pretty bad and/or be laggy. My advice, if it doesn't look good or looks washed out, use GPU scaling in your video card driver instead. With my display sub-native scaling looks much better that way.

 

[RadFX]

I run everything at the highest resolution I possibly can. Even many older games look better at 4k than below. Gaming at 4k just plain rocks unless you have a rare game which needs over 30fps and your Video card can't deliver. I don't drop my res unless I have to.

I realize it's different for people when it comes to framerates and acceptability. I personally think people are too picky. I'd much rather run 4k at lower fps than 2k or 1080p for higher fps.

 

[Frag_Maniac]

I've been wondering this myself, more specifically regarding scaling to 2560x1440 on a 4K 32-37" TV.

 

[qubit]

How well do 4K monitors scale down?

For instance, I doubt I will play any games at 4K (for now) but would like to play at 2K.

In my experience 1080p looks sharp and clean on a 4k monitor. Of course that makes sense considering every 1080p pixel scales perfectly to 4 pixels on a 4k monitor. So the pixels are just 4 times as big.

I've been wondering this myself. On my 1080p monitor, I've created a quarter HD resolution of 960x540 which looked horribly blurred when I allowed the monitor to scale it to fit the screen. A simple 1:4 pixel mapping would have looked sharp and perfect. Of course there's no option to change this. Only a 1:1 pixel mapping via the NVIDIA driver gave a sharp, but quarter sized picture.

I've not had a 4K monitor, but I suspect that most will also AA the picture and ruin it. Benq seem to be better than most with their scaling options, so might well offer a proper 1:4 scaling mode. I'll be checking them out when it comes time to upgrade.

This would be useful to me since my eyesight isn't exactly great and the tiny text on a 4K screen wouldn't be readable. If the monitor doesn't apply AA, then I could have the graphics card set to 2K for the desktop and 4K for a game or watching 4K content.

 

[EarthDog]

Someone knock the ignorance out of me...(I know there is a line for this...!!!)

How does 3840x2160 scale perfectly to 4 pixels? If I divide 3840 and 2160 by 4, I get 960x540 (1/4 the resolution of 4K). If I divide 1920 and 1080 by 4 we get 480x270 (1/4 resolution of 1080p).

I see the math working with the number of pixels in total (8,294,400 for UHD1/4K versus 2,073,600 at 1080p). But that doesn't make sense in the actual resolution?

Where did I go wrong in understanding?

 

[qubit]

@EarthDog You're not the only one to get your wires crossed with these things <qubit confesses nothing>

It's 4x, because you've got twice the number of pixels in the x axis and twice in the y axis, so 2x2=4.

 

[RCoon]

Someone knock the ignorance out of me...(I know there is a line for this...!!!)

How does 3840x2160 scale perfectly to 4 pixels? If I divide 3840 and 2160 by 4, I get 960x540 (1/4 the resolution of 4K). If I divide 1920 and 1080 by 4 we get 480x270 (1/4 resolution of 1080p).

I see the math working with the number of pixels in total (8,294,400 for UHD1/4K versus 2,073,600 at 1080p). But that doesn't make sense in the actual resolution?

Where did I go wrong in understanding?

Each single verticle pixel is stretched to two pixels, each horizontal pixel is stretched across two pixes. We're thinking of a square, not linearly.

 

[EarthDog]

@EarthDog You're not the only one to get your wires crossed with these things <qubit confesses nothing>

It's 4x, because you've got twice the number of pixels in the x axis and twice in the y axis, so 2x2=4.

Thanks but for some reason that doesn't jive in my feeble Friday morning mind...

Look at my math... If you want 1/4 of anything, you need to divide it by 4. 3840/4 and 2160/4 for UHD or what most call 4K... What you guys did was half? Right?

So it is a 2:1 resolution reduction, but yields a 4:1 TOTAL pixel reduction.

 

[RCoon]

Thanks but for some reason that doesn't jive in my feeble Friday morning mind...

Look at my math... If you want 1/4 of anything, you need to divide it by 4. 3840/4 and 2160/4 for UHD or what most call 4K... What you guys did was half? Right?

It's half resolution, quarter square pixels.

 

[P4-630]

I run everything at the highest resolution I possibly can. Even many older games look better at 4k than below. Gaming at 4k just plain rocks unless you have a rare game which needs over 30fps and your Video card can't deliver. I don't drop my res unless I have to.

I realize it's different for people when it comes to framerates and acceptability. I personally think people are too picky. I'd much rather run 4k at lower fps than 2k or 1080p for higher fps.

You must have low fps in all games at 4k, since you only have one R9 290

 

[EarthDog]

I got that just as you posted RCoon... see my ninja edit.

That explanation landed... thanks!

 

[RCoon]

So it is a 2:1 resolution reduction, but yields a 4:1 TOTAL pixel reduction.

I got that just as you posted... see my ninja edit.

Your explanation makes more sense.

The net result is that a 30" 4K monitor will look the same as a 30" 1080p monitor in terms of downscaling. Catch is most people have 24" 1080p monitors, and go up to a 28" 4K monitor. The net result is that downscaling to 1080p on a 28" screen makes everything look bigger and worse than on a 24" 1080p monitor. Jaggies for example, become more obvious.

The only way I can see 1080p downscaled being acceptable on a 4K monitor is if you're doing it on the same size monitor you had before.

 

[EarthDog]

Feels dumbed down compared to what you both explained... but I think got it... at least that portion!!

Wouldn't the resolution still need to be divided by 4, total pixel count be damned? I see from the explanations that would be a 8:1 but that is total pixel reduction, not quartering the resolution...?

(sorry... about to get some coffee)

 

[RCoon]

Wouldn't the resolution still need to be divided by 4, total pixel count be damned? I see from the explanations that would be a 8:1 but that is total pixel reduction, not quartering the resolution...?

My head hurts.

Case in point. If you're going to buy a 4K monitor, don't downscale. Use the pixels you're paying for.

EDIT: OK OK, I think I got it. So imagine "." that is our pixel. If you double the resolution vertically, and double the resolution horizontally, it takes up an additional pixel up and an additional pixel across. That means 1 pixel has now taken up four pixels in area.

 

[EarthDog]

Mine too. I suppose I just don't get it.

And +1. If you can't buy the needed hardware to support gaming on 4K, you have no business buying a 4K monitor and playing PC games on it in the first place.

 

[RCoon]

Mine too. I suppose I just don't get it.

And +1. If you can't buy the needed hardware to support gaming on 4K, you have no business buying a 4K monitor and playing PC games on it in the first place.

OK so I added a super awesome excel image above that kinda explains how 1 pixel scales to 4 with double resolution.

Double resolution, perfect 1:4 scaling.

 

[RadFX]

You must have low fps in all games at 4k, since you only have one R9 290

I get great fps actually at max or close to max settings. There are only a dozen or less games that require more than a single R9 280 to run 4k comfortably unless your a v-syncer. I personally hate V-sync and rarely have problems with tearing.

 

[qubit]

I get great fps actually at max or close to max settings. There are only a dozen or less games that require more than a single R9 280 to run 4k comfortably unless your a v-syncer. I personally hate V-sync and rarely have problems with tearing.

"Great FPS" is subjective, so what FPS numbers do you get? I'm guessing you're getting 25-40fps, maybe? If so, that's not smooth.

For me, nothing less than a smooth, vsynced solid 60fps at 4K would be good enough as anything else gives you judder. At 1080p I shoot for 120fps on my 120Hz monitor and usually get it, after adjusting game and driver settings a bit on the more demanding games.