New 72hz monitor, should I run it at 60hz?

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Och

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Just bought a new monitor for my office, LG 40WP95C-W.AUS - an ultrawide display with 5K resolution and 72hz refresh rate. I wonder if I should be running it at 60hz instead, as most youtube videos are now at 30 and 60fps, and it does not divide even into 72 so I'll be getting frame interpolation. And if I was to watch a movie, most of which are shot at 24fps, which divides even into 72, it is going to eliminate frame interpolation. I understand frame interpolation is preferable when watching movies for the "cinematic" feel.

For now I set the monitor at 60hz, but looking for advice.
 
Your monitor supports VRR, and Firefox supports playback of video with VRR enabled, so it shouldn't be an issue with Youtube if you use Firefox. I've read that Chromium-based browsers have conflicts with VRR, but I haven't used a Chromium browser in a few years. I don't recall having playback issues like tearing in 30 or 60 FPS videos the last time I did use Chrome with a 144 Hz G-SYNC monitor, though.

Set it to 72 Hz and make sure you have Freesync enabled if you have an AMD GPU, or G-SYNC Compatible if you have a NVIDIA GPU.
 
It is actually my wife's office computer, she used Chrome exclusively. I tried playing some youtube videos, and I think I they appear jerkier with 72hz refresh vs 60hz refresh, but it may be my mind playing tricks on me. Her computer has a Quadro P620, I will look for the g-sync options.

I also tried to enable HDR, but didn't like it, the monitor gets substantially darker. Either way, she uses the monitor exclusively for MS Office and Adobe Acrobat tasks, so I don't think there is any benefit to HDR or 72hz vs 60hz. We just bought the new monitor yesterday, so we were experimenting with it, and I wanted to set it up for her with the best options possible.
 
Och said:
and it does not divide even into 72 so I'll be getting frame interpolation.
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Frame interpolation is an advanced feature you'd need to ask for; some people like it but not me. You're more likely to get judder --- some frames will be displayed once and others twice, or for 30fps content, some twice and some three times; this bothers some people and not others. Using VRR to avoid judder sounds awesome!
 
I think I used the wrong term, not frame interpolation but frame pulldown - when it comes to 24fps videos on 60hz screens they use a 3:2 pulldown. I read more on it, apparently the pull down is not preferable at all, when they play movies on traditional film projectors the movies play at true 24fps. Its the low frame that is preferable for the cinematic feel, not the additional jitter introduced by the frame pulldown.

With VRR, I understand the monitor just simply adjusts its refresh to the frame rate being displayed? I also imagine it multiplies the refresh rate when possible - say if gameplay drops to 28fps it will double it at 56hz?
 
Och said:
I think I used the wrong term, not frame interpolation but frame pulldown - when it comes to 24fps videos on 60hz screens they use a 3:2 pulldown. I read more on it, apparently the pull down is not preferable at all, when they play movies on traditional film projectors the movies play at true 24fps. Its the low frame that is preferable for the cinematic feel, not the additional jitter introduced by the frame pulldown.

With VRR, I understand the monitor just simply adjusts its refresh to the frame rate being displayed? I also imagine it multiplies the refresh rate when possible - say if gameplay drops to 28fps it will double it at 56hz?
Click to expand...
I have not seen a modern screen that can't run at 24 Hz, but as you said, 72 Hz is 3:1 so it shouldn't be an issue with that kind of content.

How displays handle low framerate content varies between displays. The VRR range on your monitor is 20-72 Hz, but I can't find if and when low framerate compensation (LFC) kicks in. It's typically at max refresh rate divided by 2.5, which would be under 28-29 FPS on your monitor. LFC will run the screen at double the refresh rate and hold the image for two screen refreshes, as you say.
 
Armenius said:
I have not seen a modern screen that can't run at 24 Hz, but as you said, 72 Hz is 3:1 so it shouldn't be an issue with that kind of content.

How displays handle low framerate content varies between displays. The VRR range on your monitor is 20-72 Hz, but I can't find if and when low framerate compensation (LFC) kicks in. It's typically at max refresh rate divided by 2.5, which would be under 28-29 FPS on your monitor. LFC will run the screen at double the refresh rate and hold the image for two screen refreshes, as you say.
Click to expand...

Understood... but now I have even more question. Is flicker a concern at all with LCDs when VRR adjusts refresh rate to match fps? Most static refresh rate LCD monitors run at 60hz, and flicker is not a concern at that rate, but I remember back in the CRT days my eyes would hurt real bad at anything below 85hz. I used to always have Matrox video cards, which allowed setting refresh rate at 1hz increments, and I would always max it out to minimize flickering.

And with all of that being said, it seems like 30/60fps youtube videos inside of a Chrome browser are going to have jitter when the refresh rate is set at 72hz. It surprised me that such odd 72/144hz refresh rates are even used, 120hz makes the most sense as it divides by 24/30/60 - optimal for movies, games, and youtube videos.
 
Och said:
...Is flicker a concern at all with LCDs when VRR adjusts refresh rate to match fps? Most static refresh rate LCD monitors run at 60hz, and flicker is not a concern at that rate, but I remember back in the CRT days my eyes would hurt real bad at anything below 85hz...
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LCDs are "sample and hold" displays, which means they display an image constantly over the whole refresh period, rather than fading to black like CRTs do. Therefore there is no flickering at any refresh rate.
 
Mr Evil said:
LCDs are "sample and hold" displays, which means they display an image constantly over the whole refresh period, rather than fading to black like CRTs do. Therefore there is no flickering at any refresh rate.
Click to expand...

Good to know, thank you!
 
I don't think VRR effectively replaces video content detection to properly display frames, or simply running at a refresh rate which is divisible by the framerate of the source video.

See: your monitor isn't running at 24hz VRR, when you watch a 24fps video. And it isn't running at 30hz, when watching a 30fps YouTube video.

Apps themselves have to trigger a change for the video mode/playback to be smooth with ~24fps. I think Prime and youtube via browser, will do a simple 3:2 pulldown of the content itself, on a 60hz monitor. But they dont change yhe video mode of the monitor itself. TVs are roulettle on whether this stuff works from a PC. It's best if your global refresh is simply divisible. And if an app has options for it, tweak settings to optimize specific playback.

The Hulu app on PC doesn't do anything at all with video. And it's a judderry mess.
 
Thanks for clarifying guys. Looks like a 72hz monitor can be the best of both worlds - set it to 72 when watching 24fps movies, or set it to 60hz for youtube videos, most of which are 30/60fps.

For my wifes office use it wont matter at all, since MS office and Adobe Acrobat are not affected by the refresh rate.
 
Och said:
, or set it to 60hz for youtube videos, most of which are 30/60fps.
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I don't know if this is true. If you right click on youtube videos and click "stats for nerds" you'll see a lot of them are 24fps.

And if you really want your OCD escalated, right click on videos produced in Europe
 
Enhanced Interrogator said:
I don't know if this is true. If you right click on youtube videos and click "stats for nerds" you'll see a lot of them are 24fps.
Click to expand...

Didn't think of that... There are probably a bunch of movie/show clips on youtube with 24fps source - affirming that a 120hz monitor is ideal for everything 24/30/60.

Enhanced Interrogator said:
And if you really want your OCD escalated, right click on videos produced in Europe
Click to expand...

I remember years back download UK Top Gear shows in the late 2000s, watching them on XP/7 using I think VLC or similar player. They were shot at 25fps, and the playback on 60hz screens caused a lot of stutter. There were some codec packs that made things somewhat better.
 
Enhanced Interrogator said:
A lot of racing is recorded at 50fps too.
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Because of the old PAL tv standard I assume? Incredible how these old standards still affect us.

I imagine in the case of 25/50fps on 60/72/120/144hz monitors the playback software has to do some sort of frame interpolation to make it appear smooth?
 
Och said:
Because of the old PAL tv standard I assume? Incredible how these old standards still affect us.
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I think PAL countries still run their broadcast tv at 50Hz, because why would they change? Probably their internet tv too.

Maaaaybe they run their imported TV shows at 60Hz because almost every TV over there can do it. And a lot of their CRT TVs could run at 60Hz for video games too.

Och said:
I imagine in the case of 25/50fps on 60/72/120/144hz monitors the playback software has to do some sort of frame interpolation to make it appear smooth?
Click to expand...

If you can't change the refresh rate, you've got three choices:

1) judder or maybe you want to call it pull down, where some frames are shown more times than others (3:2 pulldown for 24fps movies on 60Hz tv is very common)

2) fuck it and run the content at your frame rate... 24fps movies are often played at 25 fps on 50hz tv systems, cause it's close and showing 11 frames twice and the 12th frame three times is gonna look awful. Maybe adjust the audio, maybe just play it fast too. Whatever. Kind of works for 24 to 25; not really doable between 50 and 60 unless you hate your viewers.

3) make shit up between the real frames. Soap opera effect. Great for sports if you want extra balls on the field.
 
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Chromium browsers adjust 24fps video to be judder free on VRR displays when full screen.
 
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