LG C4 / General OLED question

[CatTNT]

I have 1 main complaint about this TV and I'm still in  the return window for another 12-28 days. 

I have enabled HDR in windows, and am using an HDR User preset with Game Optimizer on the TV. I know that using Game Optimizer is supposed to noticeably dim the TV, but I enabled Dynamic Tone mapping to compensate for that. I like how bright it is using these two settings combined. HOWEVER, in areas of the screen with a lot of white background, I would guess any white area that covers over like 20% of the screen, that area is still very dim. Can this be be disabled at all? Can this be disabled safely, while minimizing burn in over the next 4-6 years?. The "fix" for this seems to be to enable dark mode in as many apps and website as passible, which allows me to have deep and bright colors that pop, otherwise they're not so good with a white background. I want to try disabling "Reduce Logo Brightness" which is currently set to low, but I play some games with a static HUD and I don't know if this will be safe in the long term. 

As far as I remember, according to RTINGS, this model of TV uses WOLED for the 42" and 48" panels, and QD OLED for the bigger versions. I'll only stick to 47-49" panels though, regardless if I return, or keep this TV. If this is a C4 exclusive issue, I've heard that the S90D is slightly better, or rivals the C4, but the size I would get also uses WOLED and not QD OLED, as the reviews are basing their tests on. 

[Shimejii]

Are you on windows 10 or 11? If you want to use HDR you have to be on windows 11 since 10 is pretty messed up, some workarounds but its just better on 11.

[CatTNT]

9 minutes ago, Shimejii said:

Are you on windows 10 or 11? If you want to use HDR you have to be on windows 11 since 10 is pretty messed up, some workarounds but its just better on 11.

Windows 10. I'll upgrade to 11 if I find an easy way to get rid of Ad/spyware from Win11. 

edit: It took me a while, but I've tuned my colors to what I want on the TV, everything seems perfect except large areas of white, which would indicate to me that this is a TV issue and not a windows issue. There is a separate issue with tabbing in and out of fullscreen games, which makes sense to be a windows issue, but it looks like I  can mitigate that with windows restarts and using games in borderless mode. 

[Stahlmann]

So you're talking about large white areas that are noticeably darker?

 

This is called ABL (Automatic Brightness Limiter) and it happens with every OLED and can't be turned off. OLEDs only reach their peak brightness in smaller patches and get progressively dimmer as the patch gets larger. OLEDs need this behavior to keep power consumption and heat in check.

 

OLEDS generally reach their peak brightness in up to 10% of the screen. As the bright part gets bigger, brightness will drop.

 

If you lower the HDR/SDR brightness slider in Windows, the effect becomes less noticeable and disappears completely between 5-10 and below. That's because at 5, for example, you limit the SDR content to 100 nits, which is below the C4's dimming threshold.

 

I also use my C2 in HDR Game Optimizer mode 24/7. In the TV settings, I set the brightness to 100 to make sure I'm getting the full HDR capabilities. In Windows, I set the SDR conversion slider to 5, which is still bright enough for me and ensures that I don't have to deal with ABL on the desktop and in SDR games. In actual HDR content, I never find ABL to be noticeable or distracting.

[CatTNT]

9 hours ago, Stahlmann said:

So you're talking about large white areas that are noticeably darker?

 

This is called ABL (Automatic Brightness Limiter) and it happens with every OLED and can't be turned off. OLEDs only reach their peak brightness in smaller patches and get progressively dimmer as the patch gets larger. OLEDs need this behavior to keep power consumption and heat in check.

 

OLEDS generally reach their peak brightness in up to 10% of the screen. As the bright part gets bigger, brightness will drop.

 

If you lower the HDR/SDR brightness slider in Windows, the effect becomes less noticeable and disappears completely between 5-10 and below. That's because at 5, for example, you limit the SDR content to 100 nits, which is below the C4's dimming threshold.

 

I also use my C2 in HDR Game Optimizer mode 24/7. In the TV settings, I set the brightness to 100 to make sure I'm getting the full HDR capabilities. In Windows, I set the SDR conversion slider to 5, which is still bright enough for me and ensures that I don't have to deal with ABL on the desktop and in SDR games. In actual HDR content, I never find ABL to be noticeable or distracting.

Yeah, I've been testing and the screen is so damn good with a dark background and light content that I think it worth just making everything dark mode as a mitigation. 

[circeseye]

you can change the color temperature to make it the white whiter. i didnt like the color temp of the white on my c4. that does help a lot in full field white areas.
and on win 11 you can turn off the vast majority of "spyware". but win 11 is best with hdr then 10

[ForPuffy]

On 11/25/2024 at 1:37 AM, CatTNT said:

I have 1 main complaint about this TV and I'm still in  the return window for another 12-28 days. 

I have enabled HDR in windows, and am using an HDR User preset with Game Optimizer on the TV. I know that using Game Optimizer is supposed to noticeably dim the TV, but I enabled Dynamic Tone mapping to compensate for that. I like how bright it is using these two settings combined. HOWEVER, in areas of the screen with a lot of white background, I would guess any white area that covers over like 20% of the screen, that area is still very dim. Can this be be disabled at all? Can this be disabled safely, while minimizing burn in over the next 4-6 years?. The "fix" for this seems to be to enable dark mode in as many apps and website as passible, which allows me to have deep and bright colors that pop, otherwise they're not so good with a white background. I want to try disabling "Reduce Logo Brightness" which is currently set to low, but I play some games with a static HUD and I don't know if this will be safe in the long term. 

As far as I remember, according to RTINGS, this model of TV uses WOLED for the 42" and 48" panels, and QD OLED for the bigger versions. I'll only stick to 47-49" panels though, regardless if I return, or keep this TV. If this is a C4 exclusive issue, I've heard that the S90D is slightly better, or rivals the C4, but the size I would get also uses WOLED and not QD OLED, as the reviews are basing their tests on. 

It's great to finally find someone encountering the same issue! I thought I was going crazy these past weeks.

 

My experience as an LG C4 55 owner (which should include brightness booster technology) :

 

* The main issue, as you described, is that in some areas the screen will dim. Mostly on brighter areas, and mostly in PC HDMI 2.1 HDR mode. However, there are a few things that don't quite add up:

 

- Using game optimizer picture mode, I have:

 

-> Disabled tone mapping (to exclude it as a dimming suspect)

-> Disabled energy-saving features

-> Disabled logo brightness features

-> Lowered TV brightness extensively

-> Lowered the SDR slider brightness to 0

-> Tried a various combination of picture presets and settings. It happens with most, if not all of them. IT WILL DIM the same, less noticeably in some settings.

 

But here is the big catch: If In the same spot, where it dims in-game, I switch to the "Vivid" picture mode, the screen and the whites (although distorted) will turn up to -40-50% brighter, and there will be very strong "whites" displayed along with much higher overall screen brightness. I know that the game optimizer has lower default brightness than the other modes, but the difference is considerably higher. So it's not that the screen has reached its brightness limit. This leads me to believe that this is a poor implementation of either the ABL (which cannot be disabled) or the ABSL(TPC) and GSR limiters combined.

 

And to be honest, it's immensely frustrating to be playing a game and while moving around to feel as if the sun gets covered by the clouds even though that does not happen. Not to say that all these fluctuations may be damaging to the eyesight (considering they're subtle and frequent). I've also noticed this behavior in the SDR mode from a streaming app, but the impact is usually felt at very high brightness and can be compensated by lowering it and setting "Peak Brightness" to *Medium*. I feel that this dimming situation is mainly caused by the Peak Brightness setting which is locked to "High" for the HDR picture modes, combined with the limiters.

 

Now, is this an issue for all LG C4 TVs or only some of them? Many reviews, including RTINGS mention "aggressive ABL limiter". But from my experience this makes up for a poor (G-sync compatible) PC experience. Leaving aside the fact that using the phoenix rebirth skill in FF16 will dim your screen by 50% making you wonder if fire was not supposed to be a lot brighter, the fact that it has all this occasional dimming regardless of brightness settings can be a bit dauntless.

 

Why is it not happening to more people?

 

- Most of them are using the TV for... er, watching TV. And streaming shows. Or, are using consoles which have different HDR calibrations, and as such, they will not encounter the dimming.

-Some disabled TPC/GSR in their service menu and potentially resolved the issue (while also potentially invalidating their warranty).

 

I have reached out to LG support for an official expertise. If they confirm this is how the TV is supposed to work, then I have to say that as a PC gamer it's better to stay away from the C4 (and C series in general as the C5 might not be a big improvement over the C4 from the CES coverage so far). Just be prepared to shell out more cash for the more expensive G series, or go for something else from the competition. Don't get me wrong, it's not a bad TV, but the PC HDR experience leaves a lot to be desired. But hey, as a TV and SDR gaming monitor, it's great!