LG 48CX

Tgrove said:
According to LGD, the cause is the OLED Panel not the OLED TV set. Gamma for OLED is optimized and fixed for 120Hz by establishing a fixed charging time for OLED sub-pixels. VRR is used when the frame rate is less than 120 Hz. When the OLED TV uses framerates less than 120Hz, the gamma curve is inconsistent with the frame rate. For example, a 40Hz frame rate is longer than 120Hz frame rate. Therefore, the lower frame rates results in sub pixels that are overcharged, causing flickering of dark gray images, which is noticeable for dark images rather than bright ones, because human eyes are more sensitive to low gray colors. LGD will likely solve this problem establishing multiple gamma curves optimized for lower frame rates.

https://www.oled-a.org/lgersquos-48rdquo-oled-attracting-game-monitor-buyers_9620.html
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How in the world DIDN'T they expect a massive interest for gaming? They are the only sub 50" OLED with 120Hz and VRR available and even marketed it as such?!

They're basically the only ones officially implementing HDMI 2.1 with all marquee features relevant to gaming, lol..
 
Tgrove said:
According to LGD, the cause is the OLED Panel not the OLED TV set. Gamma for OLED is optimized and fixed for 120Hz by establishing a fixed charging time for OLED sub-pixels. VRR is used when the frame rate is less than 120 Hz. When the OLED TV uses framerates less than 120Hz, the gamma curve is inconsistent with the frame rate. For example, a 40Hz frame rate is longer than 120Hz frame rate. Therefore, the lower frame rates results in sub pixels that are overcharged, causing flickering of dark gray images, which is noticeable for dark images rather than bright ones, because human eyes are more sensitive to low gray colors. LGD will likely solve this problem establishing multiple gamma curves optimized for lower frame rates.

https://www.oled-a.org/lgersquos-48rdquo-oled-attracting-game-monitor-buyers_9620.html
Click to expand...

It's interesting because it implies that a g-sync module would actually be useful here, to remedy this cleanly (like variable overdrive on LCDs). Software solutions are going to be hit and miss, I wouldn't be overly optimistic especially on current gen. Maybe the C11 will fix it?

Also the issues might actually be barely noticeable (if at all) when you are staying close to 120hz. Wish I could test all this but still don't have a GPU that can do VRR on this TV.
 
kasakka said:
equinox654 said:
What are yall running oled light and contrast in game?
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100 / 100 in HDR.

30-40 / 90 in SDR.
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Yeah HDR standards are supposed to be based on absolute values on a full scale, unlike SDR that allows you to change the brightness to taste since it is on such a narrow band.

I think they only started letting people change gamma and white point in TV OSDs and game menus for HDR because:
.. many displays labeled "HDR" were really incapable of anywhere near 1000nit
...many displays labled "HDR" were really incapable of side by side contrast
..people were using their HDR displays in improper viewing environments like bright rooms.
..game devs weren't implementing HDR properly - as well as having people play their games with all of the aforementioned inadequacies - so they prob added adjustment tools in game menus as a workaround

elvn said:
HLG is still relative which isn't true form HDR which should have absolute values.

PQ (Perceptual quantization) gamma curve is based on the characteristics of human visual perception.

HLG (Hybrid Log-Gamma) is sort of a sloppy way to make quasi HDR work with inadequate SDR based systems, live un-encoded video feed material, and lower quality quasi-HDR hardware. There's no reason games should be using the makeshift relative version other than that most of the displays people are using for HDR material are inadequate in the first place.


https://www.eizo.com/library/management/ins-and-outs-of-hdr/index2.html/

312563_lkFnvmB.png
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Tgrove said:
According to LGD, the cause is the OLED Panel not the OLED TV set. Gamma for OLED is optimized and fixed for 120Hz by establishing a fixed charging time for OLED sub-pixels. VRR is used when the frame rate is less than 120 Hz. When the OLED TV uses framerates less than 120Hz, the gamma curve is inconsistent with the frame rate. For example, a 40Hz frame rate is longer than 120Hz frame rate. Therefore, the lower frame rates results in sub pixels that are overcharged, causing flickering of dark gray images, which is noticeable for dark images rather than bright ones, because human eyes are more sensitive to low gray colors. LGD will likely solve this problem establishing multiple gamma curves optimized for lower frame rates.

https://www.oled-a.org/lgersquos-48rdquo-oled-attracting-game-monitor-buyers_9620.html
Click to expand...
kalston said:
It's interesting because it implies that a g-sync module would actually be useful here, to remedy this cleanly (like variable overdrive on LCDs). Software solutions are going to be hit and miss, I wouldn't be overly optimistic especially on current gen. Maybe the C11 will fix it?

Also the issues might actually be barely noticeable (if at all) when you are staying close to 120hz. Wish I could test all this but still don't have a GPU that can do VRR on this TV.
Click to expand...

So that quote is about the raised blacks in VRR I'm assuming. The near-black flashing fix that is getting bypassed when VRR is active, which results in near blacks being shown as raised blacks or results in near-black flashing/flickering. That frame duration explanation sounds a lot like why BFI and VRR tech generally don't play together nicely. He mentions low fpsHz in particular. The VRR stuttering on the other hand is happening at over 100fpsHZ so is a separate issue.

Since he is saying the raised blacks/near-blacks flickering is because of the subpixels and only occurs on dark greys ~ "near blacks".. I'm guessing it occurs because of the white subpixel on LG OLEDs and not just the charging duration of oled emitters in general. That's why they released firmware "fix" workarounds for near black flashing in the first place on the C9 and continued the fix in the CX line. VRR mode is just bypassing the workaround"fix" (or nullifying the effect of the workaround due to frame durations?). Regardless it is what it is as an end result. Hopefully they can provide another workaround the makes it look decent or masks it somehow even if it's not a 1:1 perfect fix.

That still doesn't address the bigger issue of VRR stuttering over 100fpsHZ from nvidia 3000 series gpus over hdmi 2.1 (and potentially from any hdmi 2.1 VRR source at over 100fpsHZ as far as we know currently).
 
elvn said:
That still doesn't address the bigger issue of VRR stuttering over 100fpsHZ from nvidia 3000 series gpus over hdmi 2.1 (and potentially from any hdmi 2.1 VRR source at over 100fpsHZ as far as we know currently).
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That is already fixed on .26 firmware with 4k 120Hz 10bit 444 limited. (rgb full 10but has the stuttering issue - but also more banding, so 444 limited might be preferable either way unless they also fix the rgb-full banding in later firmware as well)
 
Morkai said:
That is already fixed on .26 firmware with 4k 120Hz 10bit 444 limited. (rgb full 10but has the stuttering issue - but also more banding, so 444 limited might be preferable either way unless they also fix the rgb-full banding in later firmware as well)
Click to expand...
I'm wondering if there may be more glitches with RGB Full vs RGB Limited other than VRR?
 
Hello!!! I’m looking to buy a new Oled CX. I’m worried about the raised blacks with VRR. With the latest LG C9 firmware they solved this problem? And the flickering image? Do you think xbox series x will have a different VRR? Thanks
 
My boy took my shit away. Horizon zero dawn at 4k 60 hdr on a 2070 super max settings. I can tell its not locked 60 but gsync seems to be doing its job. Feels a hell of a lot smoother than the ps4 pro. Not to mention the image quality difference.

Can't wait for 3080 stock or 6800xt reviews.
 

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Morkai said:
That is already fixed on .26 firmware with 4k 120Hz 10bit 444 limited. (rgb full 10but has the stuttering issue - but also more banding, so 444 limited might be preferable either way unless they also fix the rgb-full banding in later firmware as well)
Click to expand...
How are people getting .26FW?
 
netjack said:
How are people getting .26FW?
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.26 was out for a short bit in early October... many grabbed it and applied go US, Canadian, South Korean units. Works fine on all NTSC units. Doesnt work on any EU/EMEA units.

Some guys also hosted the zip archive after LG pulled it (South Korean site now also lists .25 just like US does after it finally caught up).

Waiting on something newer now, hopefully a few more firmware updates before the CXI/CXIIs series steal the show.
 
Perscitus said:
.26 was out for a short bit in early October... many grabbed it and applied go US, Canadian, South Korean units. Works fine on all NTSC units. Doesnt work on any EU/EMEA units.
Click to expand...
I have a EU unit (OLED55CX6LA), the .26 firmware was up briefly on the lg uk site.
 
equinox654 said:
My boy took my shit away. Horizon zero dawn at 4k 60 hdr on a 2070 super max settings. I can tell its not locked 60 but gsync seems to be doing its job. Feels a hell of a lot smoother than the ps4 pro. Not to mention the image quality difference.

Can't wait for 3080 stock or 6800xt reviews.
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maxresdefault.jpg
 
mrvicco said:
Well we have paid for a gsync oled , wich doesn’t work fine , so why pay more for something that doesn’t work as it should do?
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Because I mainly bought it for the OLED, HDR and 55" part.

G-Sync works fine up to 100Hz it seems which - right now - is enough for me as I can't push AAA titles beyond 120Hz anyways. And eve then 4:2:0 120Hz would be better than what I currently get on my 2070 Super.. The OLED for me is just for casual, fun, relaxed gaming entertainment.. thay being said: 444 RGB 120Hz VRR and DV raised blacks need to be fixed. Period.

The only things I'm interested competitively nowadays would be simracing, but that's reserved for VR - which again I want something more powerful for than my 2070S..

So yeah, I'm stupid hungry for something to sink another 1k into. nVidia failed hard, both in pricing for the 3090 and availability of the 3080. That's the third botched launch in a row for team green - so let's see what team red can offer..
 
Is it 120hz in general thats broken or just with gsync? Because if it's just gsync... when I can secure a new card. Ill just turn off gsync.

The lcd smearing bothered me more than tearing anyway.

Even with out gsync. Id pick the cx over the Asus pg348q ultrawide I replaced every day of the week.
 
equinox654 said:
Is it 120hz in general thats broken or just with gsync? Because if it's just gsync... when I can secure a new card. Ill just turn off gsync.

The lcd smearing bothered me more than tearing anyway.

Even with out gsync. Id pick the cx over the Asus pg348q ultrawide I replaced every day of the week.
Click to expand...

Seems like running triple digit fps (so 100+) fps causes stuttering, but only when running 10Bit 444 at the same time. People have said that dropping back to 8Bit 420 resolves the stuttering problem. The other issue is noticeable flickering if you are running near the bottom end of the VRR window (so 40-50) fps, this happens even if are you running 8Bit 420 like I am. So for now, as long as you run well above 60fps and in 8Bit 420 then you shouldn't be having any major issues with gsync.
 
4K120 4:4:4 10-bit runs great. It only runs into issues (at the moment) if you enable gsync. Even then, if you stay under 100 FPS, it's fine. You can also run 4K120 4:2:0 8-bit and gsync runs great there. It just feels like LG is having some issues when having really high bandwidth signals + gsync sent to it.
 
madpistol said:
4K120 4:4:4 10-bit runs great. It only runs into issues (at the moment) if you enable gsync. Even then, if you stay under 100 FPS, it's fine. You can also run 4K120 4:2:0 8-bit and gsync runs great there. It just feels like LG is having some issues when having really high bandwidth signals + gsync sent to it.
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The more I think about it, the more I think the issue is that the TVs processor might not be able to keep up with what is being sent to it when VRR is enabled. Would explain why dropping chroma down to 4:2:0 or lowing the maximum refresh rate "fixes" it. If so, they could probably optimize things a bit more and push it as a FW update.
 
Advil said:
Unfortunately the HDR situation isn't cut and dry in Windows. I prefer to leave HDR off on the desktop, set my HDR games to full screen mode, and then when you turn on HDR in the game it will kick on HDR on the screen only when the game is running and fullscreen. Automatic... easy... and SDR content will look best this way.

But, there are a few games that only enable HDR if the Windows slider is already "on". So, you have to just live with this and be ready to turn it on and off as needed in Windows, OR try to leave HDR mode on in Windows and get your SDR brightness slider set as properly as you can. I don't consider this ideal... but it's not terrible.
Click to expand...
Yeah, but some titles absolutely hate the Windows OSD with HDR enabled, causing the display to briefly blank as the display switches to SDR then immediately back to HDR. In theory, Borderless Fullscreen should address this, but at least one title I own (CoD: Warzone) this does *not* work and I have to play in an actual fullscreen window for HDR to work properly.

And don't even get me started on older titles that don't have a clue what HDR even is.

So yeah, the HDR situation in Windows is *not* ideal.
 
Hello,

I have been a long time reader but first time posting here.
I recently decided to go for it and ordered the LG OLED 48CX
I hope to pair it with a RTX 3080 when ever that ships I ordered a moth ago but still no shipping date.....

I understand that VRR grey black shift issue probably wont be fixed maybe lessened if we are lucky.
But because every other comparative monitor runs well over 2 000 euros. Yes VRR would work better, maybe less ghosting and I would probably get better color accuracy but loose on contrast and black depth I decided that the trade off is worth it.

But I have some questions on how to set it up.
I hope you guys are willing to help me out a bit here.
1. I really dislike headphones I want 5.1.2 sounds so I was thinking to pair this with a Samsung HW-Q950T. Would this work if I connect the 3080 to the 48CX then use the EARK port to connect to the Samsung HW-Q950T. I know that to get Atmos to work I need to buy the APP from Microsoft store. I read that there is a sound lag using this method? Does this only happen at high FPS?
As I understand all AVR right now have a HDMI 2.1 hardware bug so I can not connect to the AVR then to the TV 48CX.
Is anybody using this or a similar setup using the EARK port?
As I understand I can use a normal 18gig cable to connect the TV to a sound bar no need for a 48gig cable?
2. I am confused by all the topics on 48gig HDMI cables not working. Why is this shouldn't all cables rated at 48gigs work to carry the full 4k 120HZ signal? I know that there is no official certification for HDMI 2.1 cables exists but shouldn't any 48gig cable work?
I do not need a long cable 2m will do it. Do I really need to spend 100 or 200 euros on a cable? I mean all those cables are digital right? So there should be no real difference if it has the required 48gig bandwith? No?
Would a normal cable like this one work?
Cable Matters 3-Pack 48Gbps Ultra 8K HDMI Cable with 8K@120Hz and HDR Support for PS5, Xbox Series X/S, RTX 3080 / RTX 3090, AMD RX 6800 / RX 6900, Apple TV and More - 2m
https://www.amazon.de/-/en/Cable-Matters-3-Pack-48Gbps-Support/dp/B081NXV3ZR/ref=sr_1_8?crid=XQGZB21MYACG&dchild=1&keywords=cable+matters+3er-pack+48gbps+ultra+8k+hdmi-kabel&qid=1604362116&sprefix=Cable+Matters+3-Pack+48Gbps,aps,225&sr=8-8&th=1
Or do I really need some sort of special cable? If so could someone recommend me a cable that would work?
3. Lastly is there some sort of guide how to set this up for PC use?
I know that I have to:
Switch to PC mode
Cap the VRR herz at 115 or 90 until the patch hits
Set the resolution in the Nvidia control panel
What about HDR how do I set that up?
What about overdrive should I use it or no set to auto?
Any other settings that I should change colors brightness or something else?

Thank you for your time guys
 
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MacOS is great at handling font rendering in a sensible way even if it does not support BGR. You can just disable RGB subpixel AA and it works fine without becoming the odd shit Windows does with Cleartype disabled.

But where it just fails so hard is that it has no toggles for bit depth or chroma subsampling. So what does it do on my new work MBP 2019? It defaults to 4K 10-bit 4:2:0! And there is no way to change that to run at 8-bit 4:4:4! All the fixes for this are stuff like EDID overrides. I will probably have to try to dump EDID from Windows, use CRU to remove 10-bit support and see if I can get it loaded as an EDID override in MacOS.

I never had this issue with my MBP 2016 simply because it did not support things like HDR. Speaking of which, HDR support is just not visible as an option as it's yet another thing MacOS "smartly" detects whether it shows or not, just like upscaling resolutions! Even apps like SwitchResX can't toggle bit depth, chroma subsampling or HDR support.

EDIT: Just for shits and giggles I tried using my CableMatters USB-C to DP 1.4 adapter with the Club3D DP 1.4 -> HDMI 2.1 adapter. Surprisingly it works just fine, but suffers from the same issues as the USB-C to HDMI 2.0 adapter. I am guessing the problem is with the display EDID.

EDIT2: Solved this by editing the EDID in Custom Resolution Utility and removing references to 10 and 12 bit color. Stupid but it works. HDR option is still absent.
 
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NukeDukem said:


:(
Click to expand...


Just to clarify, does this gamma issue only manifest when VRR is enabled? If I disable VRR, and I use vsync to lock 60Hz or 120Hz, I assume there is no issue because the screen is still refreshing at 120Hz as long as VRR is disabled?

I have one of these on the way (finally) and this gives me pause. If it's OK at 60Hz and 120Hz without VRR, it may still be OK for me. Hmmm.
 
But that's only for console VRR correct ? Gsync at 120hz should be fixed in the next firmware ?
 
He wasn't talking about VRR/G-sync stuttering at over 100fpsHZ.. He's talking about raised blacks when VRR is enabled, which happens because of fpsHz fluctuating below 120fpsHZ. He suspects no fix until a new model line of LG OLED TV (next year?) as it would require a new hardware scaling capable of the different gammas for different Hz.

He said the LG OLED TV's gamma are optimized for 120hz so when your frame rate fluctuates on a roller coaster of actual frame rates +/- from your frame rate average, the oled emitters remain overcharged. So they are brighter throughout the frame rate graph and gameplay since the frame rate goes down (and up) constantly.

I don't know if the rasied black amount could be minimized by running a frame rate graph whose bottom was more like 100fpsHZ.. for example

100fpsHZ <<<<< 117fpsHz average (120fpsHz average capped to 117) >>> capped so no higher here

Some games only "droop" 15fps from average... but others do -30fps from average so those might be worse overcharging even with close to 120fpsHz average.

Having to keep a frame rate so close to the cap would really reduce the value of using VRR in the first place though unfortunately.

--------------

That said the raised blacks probably aren't that bad or more people would be complaining about them. I've heard it's like 1 notch worth on a "move the slider until you can barely see this symbol" menu in games. Most noticeable in a proper dim to dark viewing environment.
 
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elvn said:
He wasn't talking about VRR/G-sync stuttering at over 100fpsHZ.. He's talking about raised blacks when VRR is enabled, which happens because of fpsHz fluctuating below 120fpsHZ. He suspects no fix until a new model line of LG OLED TV (next year?) as it would require a new hardware scaling capable of the different gammas for different Hz.

He said the LG OLED TV's gamma are optimized for 120hz so when your frame rate fluctuates on a roller coaster of actual frame rates +/- from your frame rate average, the oled emitters remain overcharged. So they are brighter throughout the frame rate graph and gameplay since the frame rate goes down (and up) constantly.

I don't know if the rasied black amount could be minimized by running a frame rate graph whose bottom was more like 100fpsHZ.. for example

100fpsHZ <<<<< 117fpsHz average (120fpsHz average capped to 117) >>> capped so no higher here

Some games only "droop" 15fps from average... but others do -30fps from average so those might be worse overcharging even with close to 120fpsHz average.

Having to keep a frame rate so close to the cap would really reduce the value of using VRR in the first place though unfortunately.

--------------

That said the raised blacks probably aren't that bad or more people would be complaining about them. I've heard it's like 1 notch worth on a "move the slider until you can barely see this symbol" menu in games. Most noticeable in a proper dim to dark viewing environment.
Click to expand...

That could be possible. Most games I been playing on my CX are ones that I could run at pretty high fps off a 2080 Ti and honestly raised near blacks hasn't been any sort of eyesore issue for me. You really don't want to be running in the lower end of the VRR window anyways or else you start to get noticeable flickering. Pretty sure it still flickers at higher fps but probably it's probably more subtle so it's unnoticeable. I failed to notice any flickering until I started playing GW2 and it was running in the 40's fps so it's possible that raised near blacks become more obvious the further away from 120Hz you are. If anything, the raised black level in dolby vision is more of an eyesore vs VRR raised near blacks...it's almost like you're watching on an IPS panel or something with grey blacks.
 
elvn said:
He wasn't talking about VRR/G-sync stuttering at over 100fpsHZ.. He's talking about raised blacks when VRR is enabled, which happens because of fpsHz fluctuating below 120fpsHZ. He suspects no fix until a new model line of LG OLED TV (next year?) as it would require a new hardware scaling capable of the different gammas for different Hz.

He said the LG OLED TV's gamma are optimized for 120hz so when your frame rate fluctuates on a roller coaster of actual frame rates +/- from your frame rate average, the oled emitters remain overcharged. So they are brighter throughout the frame rate graph and gameplay since the frame rate goes down (and up) constantly.

I don't know if the rasied black amount could be minimized by running a frame rate graph whose bottom was more like 100fpsHZ.. for example

100fpsHZ <<<<< 117fpsHz average (120fpsHz average capped to 117) >>> capped so no higher here

Some games only "droop" 15fps from average... but others do -30fps from average so those might be worse overcharging even with close to 120fpsHz average.

Having to keep a frame rate so close to the cap would really reduce the value of using VRR in the first place though unfortunately.

--------------

That said the raised blacks probably aren't that bad or more people would be complaining about them. I've heard it's like 1 notch worth on a "move the slider until you can barely see this symbol" menu in games. Most noticeable in a proper dim to dark viewing environment.
Click to expand...


Yeah, the way I understand it is the further you get from the max refresh rate the more lifted the blacks can become. So if you were only averaging lower fps you could fix this by settings the refresh rate lower.

For example if you're only getting 50 FPS you could switch from 4k@120hz VRR signal to a 4k@60hz VRR signal to minimize it.

It's basically the same problem a lot of the freesync monitors have with pixel overdrive. The GSYNC hardware module varies the overdrive based on the frame rate, and most freesync monitors don't have that capability.
 
sharknice said:
Yeah, the way I understand it is the further you get from the max refresh rate the more lifted the blacks can become. So if you were only averaging lower fps you could fix this by settings the refresh rate lower.

For example if you're only getting 50 FPS you could switch from 4k@120hz VRR signal to a 4k@60hz VRR signal to minimize it.

It's basically the same problem a lot of the freesync monitors have with pixel overdrive. The GSYNC hardware module varies the overdrive based on the frame rate, and most freesync monitors don't have that capability.
Click to expand...

Yeah the Gsync module was absolutely worth it. It was pretty irritating to see people hate on it saying it was no better than freesync but being charged a premium regardless. The experience of having a gsync module vs no gsync module is more than worth the price increase that comes with it as the experience is just flat out better.
 
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It's about distance. If you want to not move your head around you need to get it out away from you. Anywhere from 48-60" away. Depends on what you like. Mine is at about 56"... yes I use text scaling. I have two large panels on my desk that are at middle distance vision.
 
All this raised black issue and flickering when frame rate drops only pertains to 4k? Or is it the same problem in 1440p?
 
sharknice said:
Yeah, the way I understand it is the further you get from the max refresh rate the more lifted the blacks can become. So if you were only averaging lower fps you could fix this by settings the refresh rate lower.

For example if you're only getting 50 FPS you could switch from 4k@120hz VRR signal to a 4k@60hz VRR signal to minimize it.

It's basically the same problem a lot of the freesync monitors have with pixel overdrive. The GSYNC hardware module varies the overdrive based on the frame rate, and most freesync monitors don't have that capability.
Click to expand...

Vincent said the panel gamma is calibrated for 120hz ~ 8.3ms frames.. so the farther from that you get from that with VRR, the more over-energized the frames are because their durations are longer.

Would it be possible to set the display to lower Hz as you are suggesting, then calibrate the gamma manually to a lower start point at 100Hz or 60Hz as far as the ODS settings go? - I'm not sure that there isn't a curve built in to the TV's hardware/scaler based on the 120hz scale that would take priority when VRR is active from what Vincent was saying in that video...
 
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