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WOLED and QD-OLED line pattern/PWM flickering dithering in dark content megathread

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18K views 62 replies 28 participants last post by  Avadakedvr  
#1 · (Edited)
Hello,
It seems all 2024 WOLED and QD-OLED panels are affected with some kind of PWM-like flickering dithering that degrades the picture quality.
Please look at the following pictures :
LG CX(gray test image, red subpixel is off because it wasn't set to the same picture mode)
Image

LG G4(same test image!!!)
Image

Image

Image


QD-OLED has similar flickering, but instead of pixels being turned on and off in a checkerboard pattern, it is flickering with a vertical pattern of brighter and dimmer pixel columns :
(note: this is a 3rd gen QD-OLED monitor rather than a TV)
Image



In the case of WOLED, the pattern looks like diagonal lines, is visible when tracking moving objects and for static objects it is briefly visible when the eye blinks or moves to focus on another object. It is particularly bad in night scenes or scenes that contain vegetation under the shadow but in general ANY color that will make the panel dimly lit one or more subpixel(s) is affected. The threshold appears to be approximatively RGB 50 with full brightness, the threshold becomes higher as the brightness goes lower and i speculate the reason the threshold is so high is partly because of MLA so perhaps the C4's PWM flicker threshold is lower?

As for QD-OLED, i see it when a dark object moves laterally, it looks like a scissor pattern. The threshold seems to be approximatively RGB 20, but the pattern is very difficult to capture as it isn't ON/OFF like LG so it may actually be higher.

The patterns are very sharply visible(the pattern does not seem to move or change) when the eye tracks an object that moves at the same speed(in pixels per second) as the number of times the flickering occurs, but it is ever present even if the image is static and as mentioned above can still be seen in static images.

It persists in the integrated image test and WebOS interface, and i have been unable to find any way of eliminating this processing, only worsening it by reducing the brightness, so i suppose it is related to the end pixel illumination value rather than the input image.

It is not limited to LG or Samsung, i can confirm that at least Philips's equivalent of the G4 has the same issue.

I made this thread to spread awareness of this major downgrade, as this ruins the picture quality for people who are using these TVs are monitors(people are doing this since the C9 gen at least) and it may still be seen as an unnatural(not present in the source image) grain effect from afar. It may also cause eye strain.

Please reply if you are affected by the issue or know anything really, videos and pictures of the flickering in action are appreciated too. All i ask is that you don't post LG support-tier replies such as insisting that it is dirty screen effect or copy pastes of what a user said with "it's normal" or other corporate speak.

edit: Forgot to mention LG's official marketing names this "Detail Enhancer", Samsung doesn't have an official name as far as i know but LG does make completely false statements in their marketing material however, they state it is used to fight banding but it is believed to be a low quality mitigation against overshoot, the quality leaves a lot to be desired considering it's always there even in static images and video that are unlikely to provoke banding or overshoot artifacts.

Also, adding a 120FPS video of the flickering where it can be seen that even RGB 255,255,255(full strength white) flickers the red and blue subpixels : flickering.mp4 (120fps playback should work within the browser, else download the video first)
 
#2 ·
I definitely see the diagonal lines on my 77" G4, but would never sit close enough to the TV to see it in regular viewing.

I found it using a test sample mentioned on a reddit thread ( ) with Disney+ Acolyte S1E4 around the 5:50 mark, right before the "introduction" plays. You see it a lot where the bridge is in the Acolyte episode.

Hard to capture a picture of it occurring because when you pause the screen, the diagonal lines go away - it is only visible during motion.

It isn't limited to streaming content, Dolby Vision or HDR10 content though, it happens all the time. For example from the AppleTV Home Screen, if I highlight the Disney+ logo and then move away from it so the icon gets bigger and then smaller - I see the diagonal lines in the Disney+ logo as it is moving.

The diagonal lines are completely visible in real life, not just during slow motion - but it is a lot easier to capture it on video with slow motion.

I made 2 short videos using my iPhone in Slowmotion to really show off the diagonal lines occurring:

Acolyte:

AppleTV home screen:

At normal viewing distances this isn't visible at all though.
 
#4 ·
I want to enjoy the TV, but this is a straight up downgrade. The brightness is certainly best on the new models but what's the point if OLED's strength, dark detail is ruined?
The flickering gives me eye strain when the brightness is turned down or content that provokes the flickering is displayed for long periods of time.
The visible grain it causes in very dark content just looks bad, DSE is preferable since it at least appears temporally stable when it is visible.
 
#7 · (Edited)
I’ll share with you my experience with this year’s LG C4 and G4 models. I decided to replace the C7 in my living room, which had suffered burn-in, with something new. After reading tons of reviews, I bought the G4 77 during Black Friday, and for a few days, it was amazing. I was thrilled with the picture quality, colors, and everything else.

But after a few days, I started experiencing severe eye pain, tingling, burning, dryness, and white spots. I was convinced it was due to the MLA coating because I’d never had any issues with other OLEDs. I have a CX55 in the bedroom and a CX48 on my desk. I returned the G4 and bought the C4 instead. Again, for the first few days, everything was fine, but then the same problems started, though maybe slightly less intense—still burning, itching, and a feeling of pressure in my eyes. When I turn on the C4, it feels like there’s some kind of flicker on it.

I’m devastated because LG has ruined one of the best TV panels for me.
 
#10 ·
I’ll share with you my experience with this year’s LG C4 and G4 models. I decided to replace the C7 in my living room, which had suffered burn-in, with something new. After reading tons of reviews, I bought the G4 77 during Black Friday, and for a few days, it was amazing. I was thrilled with the picture quality, colors, and everything else.

But after a few days, I started experiencing severe eye pain, tingling, burning, dryness, and white spots. I was convinced it was due to the MLA coating because I’d never had any issues with other OLEDs. I have a CX55 in the bedroom and a CX48 on my desk. I returned the G4 and bought the C4 instead. Again, for the first few days, everything was fine, but then the same problems started, though maybe slightly less intense—still burning, itching, and a feeling of pressure in my eyes. When I turn on the C4, it feels like there’s some kind of flicker on it.

I’m devastated because LG has ruined one of the best TV panels for me.
Same I don't recall experience strain with my Sony oled a8f that came out in 2018
 
#8 ·
Man Kudos to you for pointing this out!
Every other user I've talked to believes what RTINGS has to say for nearly all OLED TVs by defaul= No PWM
I don't think people realise how bad it is for our vision, primarily because of varying sensitivity we have but in the end the raw fact is our eyes are being burdened with flickering. Those who are not sensitive to it might develop sensitivity later. We might see more people wearing glasses sooner than later.
I can barely stand my LG G4 for more than a hour. I think I've axed my foot selling 6 years old Sony OLED that never gave me eye strain
 
#32 · (Edited)
No PWM for WOLED is kind of a lie.
Old WBC-type panels(until CX, early C1) and new WBE/Evo seem to refresh the screen differently?
WBE/Evo refreshes in a way that cause a small dark line to sometimes appear when taking a photo with fast shutter speeds.
WBC refreshes in a way that has a slight brightness drop on slow motion video.
IME WBC refresh behavior didn't cause me eye strain but it shouldn't be considered 100% PWM free like a DC dimmed VA LCD.
I'd investigate with a camera that has a super high shutter speed but i don't have one.
 
#11 ·
QD-OLED has similar flickering, but instead of pixels being turned on and off in a checkerboard pattern, it is flickering with a vertical pattern of brighter and dimmer pixel columns :
(note: this is a 3rd gen QD-OLED monitor rather than a TV)
View attachment 3658994
Does this only occur at 144hz or also at lower framerates ?
 
#33 ·
I can confirm it happened at 120 and 144hz refresh rates, and i remember 144hz being slightly less worse.
I think it's tied to the refresh rate, the TCON board has to refresh the pixels to change the flicker pattern and i doubt it could decouple the "detail enhancer" flickering from the pixel refresh logic.
 
#36 ·
It is a real issue, if you watch from afar like in a living room it will look like a grain effect but at a gaming distance it's omnipresent on colors with a subpixel under the dithering threshold. Even if you do not see it the flicker will still cause eye strain since the pixels are alternating between ON and OFF at 120hz.
The way it works is by applying a mask filter that turns off two subpixels and boosts the illumination value of the remaining 0 to 2 other subpixels in a mesh pattern if they are under a certain illumination value, on each refresh cycle the mask is inverted such that only half the affected subpixels are turned on at a given time.
 
#14 ·
Is this an issue with my 2024 Sony A95L ?
I can’t see it, but maybe I’m missing something.
 
#16 ·
omg yes, I've been pulling my hair out trying to figure out if this is a problem with just my panel or the tech.... and I guess it's the tech :(

I have the Dell Alienware AW2725DF (QD-OLED) and I'm getting this exact dithering only in certain dark scenes when the scene is moving laterally (or actually if I move my head laterally too as silly as that sounds lol). Unfortunately, I noticed this problem a little too late, and I can't refund it now, but this issue is annoying me enough that I might just sell the monitor and get the Samsung G6 VA panel (LS27BG652ENXGO), which I hear is the best VA panel out there. Like you said, what's the point of spending all this money on an OLED just to have its main selling point degraded with artifacts.
 
#25 ·
Yes, Vincent confirmed that the dithering algorithm and the diagonale lines are still present on the G5 but would be nice if a G5 owner would test some footage to let us know if the issue is as agresiv as on the G4. Vincent said if you are at least 3 feet away you cant spot them.
What's your experiences with the G4, what is the distance the lines starts to be perceivable on 65/77 inch TV?
 
#26 ·
Yes, Vincent confirmed that the dithering algorithm and the diagonale lines are still present on the G5 but would be nice if a G5 owner would test some footage to let us know if the issue is as agresiv as on the G4. Vincent said if you are at least 3 feet away you cant spot them.
What's your experiences with the G4, what is the distance the lines starts to be perceivable on 65/77 inch TV?
I didn't see the lines on C4 83 and G4 77 from a distance; it looked more like a grainy picture effect and caused eye strain. The strain was more intense on G4 77. In addition to itching and eye fatigue on C4 I started seeing white spots and experiencing severe headaches on G4.
 
#35 ·
I made test videos that should make it easier to see dithering artifacts, you can download them here :
Files are made for 4K120 TVs and 1440p240 monitors, choose the one for your display resolution and refresh rate. The files with QD-OLED in the filename have a background color optimized for QD-oled's bigger green subpixels.
To use it it's very simple, play the video in fullscreen on your TV/monitor through the TV itself or your gaming PC and track the moving WRGB bands with your eyes, if the rate the dithering updates matches the number of pixels per second of movement you will immediately see the dithering in action.

The bar patterns alternate in three versions : the first has gradients, the second attempts to stack Detail "enhancer"'s dithering in such a way that it would result in black for at least one color depending on when you started the video, the third just has flat colors.
Please give feedback if there's any problem, i've tried to tweak it so it would work on both 2024+ WOLED and QD-OLED monitors, but i got my G4 refunded so i couldn't test it on an affected WOLED immediately. I'm looking for any comments on the size of bars(bars are hard to track if too big, and if too small the dithering is hard to see too), and wether it is too dark.(QD-oled dithering is most visible on very dark colors compared to WOLED where even bright white can dither)
If it doesn't work, try to change the playback speed to 0.5x or 2.0x.(for monitors, temporarily lower the refresh rate to 240.)
 
#41 · (Edited)
According to viperreus on the other thread about the issue Samsung QD-OLED TVs don't have it, only QD-OLED monitors but perhaps samsung has gone back to the old style of dithering so while there may still be some form of dithering it is at least tolerable?
By that metric QD-OLED would be the superior choice if fringing isn't a concern for you.(depends on pixel density, distance and if you watch HDR things with many small bright white highlights etc...)
 
#40 ·
Such an interesting thread, I wait for years to upgrade my lcd screen with those awful plate of Grey and suddenly I found out that LG g5 has posterisation and no software fix available yet... I was hoping that Sony bravia 8 2 would be the solution but you seems to say that all woled and qd oled are involved? Is this dithering noticeable at a distance more than 2 meters? Why miniled would not be affected? Thanks by advance
 
#42 ·
The dithering is visible from afar and on static images, it looks like grain.
Diagonal lines are confirmed to be visible in games on 42inch even when sitting from over a meter.
It depends on the eye's ability to perceive detail, from a closer distance diagonal lines are visible, from a large distance it may look like grain, either way it is flickering and can cause eye strain.
Miniled can flicker like any backlight that uses PWM dimming, if it uses DC dimming it shouldn't flicker.
It seems QD-OLED has this line pattern dithering only on monitors, but more proof would be required before being 100% certain as we know S95B had dithering that caused loss of saturation instead.
 
#46 ·
I don't believe there is any definitive fix for the picture quality degradations LG implemented on purpose.(dithering, CPC outside filmmaker mode, forced sharpening even in filmmaker mode)
CPC(vignetting effect on large gradients or grey) can be reduced in the full service menu(use ColorControl) but not turned off.(worst is it's a power saving "feature", it's only there to save power or at least that's the intent)
I couldn't find anything in the service menu related to the other degradations, at least for the G4.
https://www.avsforum.com/threads/lg-2024-tv-oled-cpc-megathread-vignetting-in-games-pc-mode.3308343/ (this applies to 2025 TVs too, someone on rtings comments complained about the same exact thing)
 
#54 ·
Anyone know if it’s safe to buy a new LG B3 77”? Found a pretty killer deal on one and pushed the button!

Like many others I got a C4 recently, that I unfortunately had to return due to eye strain/pain and headaches. I have owned both WBC and WBE panels for years without any issues and they are still fine to watch post C4.
 
#56 ·
Bummer the LG 5 was on my short list! May as well wait for the new RGB panel tech in the 116ux or from others in 2026...