Products to try or avoid? PWM Flicker and Temporal Dithering Testing
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The one I have listed in my original post for this discussion in the table: LG 27gp95r-b
I still need to find the specific panel model. It was not present or maybe as noticeable when brand new out of the box only a few months ago.
Edit update:
The horizontal lines are what's shown in these videos expect mine is less noticeable.
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finding panel for LG 27gp95r-b high refresh rate monitor.
- https://www.panelook.com/LM270WR8-SSE1_LG_Display_27.0_LCM_overview_64259.html
- https://www.panelook.com/LM270WR8-SSD1_LG_Display_27.0_LCM_overview_62942.html
- https://www.panelook.com/LM270WR8-SSA1_LG_Display_27.0_LCM_overview_48193.html
If not one of the above , some similar panel closest in spec to the the third one (SSA1)
HWiNFO64 returns LG [Unknown Model: GSM5BBF]
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Nord N30 max brightness PWM:
It looks bad but I can handle this much better than the oled samsung s10+ at max screen brightness.
versus samsung s10+:
All measurements at 20dB gain on pda100a2 photodetector.
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HKC MB140CS01-4 is a compatible FHD lcd panel for T480 and most likely T480s thinkpad laptops.
https://www.panelook.com/MB140CS01-4_HKC_14.0_LCM_overview_60997.html
100% brightness still shows some flicker despite stating dc dimming in panelook. Tested using a T480, linux mint 21.3, full white rgb(255, 255, 255) patch. Not subjectively comfortable compared to 7i panel (see posts above).
(thorlabs pda100a2 detector at 20dB gain)
Zooming in with shorter 5ms timescale reveals 60hz flicker.
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photon78s BTW, I tried a Nord N30 and surprisingly, it showed no easily detectable PWM at max brightness with the 240hz iPhone 14 Pro camera (which is otherwise good at detecting PWM on devices that other cameras don't catch)
Unfortunately, despite passing my PWM test, the screen still sucks IMO and is unusable for me. I'm actually surprised you can use it as your daily phone
The weird thing though is that it sucks in a totally different way than I was expecting.
Usually with "bad screens" on iPhones for example (on both LCD and OLED ones) I see "oversharpening artifacts with obvious color fringing, constant twitching motion everywhere, noisy looking white backgrounds, eyestrain that I can physically feel after looking away"
On the N30, I actually don't feel most of those symptoms in quite the same way, the screen feels more still than usual and I actually don't feel much "physical pressure behind the eyes" at all!
However, instead, what I feel is just intense blurriness when looking at the N30 display, nothing is sharp and everything seems to have "artificially softened" edges. The PPI of the 1080p display is great in theory and I can't see the pixel grid, but despite that, everything looks blurry. There also seems to be weird very subtle black shadows around all text and borders/dividers.
(It's a totally different feeling from looking at a "low res" display that "still feels sharp but is just pixelated looking". The N30 is actually blurry and makes me feel like I need glasses even if I bring it close to me)
After using the N30 for just 20-30 minutes I feel extremely tired to the point I want to fall asleep and lots of brain fog/confusion.
The symptoms are actually very unique from my typical FRC, PWM, or "Apple device/AMD/modern Intel graphics post-processing" symptoms — but still affect reading and productivity just as bad
The main symptom it does share with Apple devices and modern Intel graphics is the false 3D effect, however it's more subtle than usual. Didn't notice it at first but became obvious on certain content.
(The presence of that effect is already enough of a dealbreaker to make me return it IMO)
After taking a break, I looked at my old Redmi 3 for 10 minutes to reorient myself. After that I already felt like I had a decent amount of my energy back and I could finally see clear and normally again!!
White backgrounds are also very strange on the N30, because they both feel harsh and not harsh at the same time. They aren't noisy or flickery feeling like on iPhones, but they still feel way too bright compared to everything else.
In general there's also way too much reflectiveness to the N30 display.
Modern iPhones use some kind of oversharpening effect. Meanwhile, the N30 also definitely has post-processing but causes undersharpening instead.
Meanwhile, the 720p display on my Xiaomi Redmi 3, which actually has lower PPI (and even has some mild PWM at max brightness), is totally fine and everything appears as crisp as it should.
I actually put them side by side and the N30 was so obviously blurry compared to it.
I even showed the N30 to a friend who's otherwise not screen sensitive at all (they use an iPhone 12 that I can't even stand looking at) and even they said the N30 looked blurry and felt difficult to read
To repeat, it's not because of the PPI or resolution, because the physical density is high enough where I can't see the pixel grid.
It's the software, GPU or panel controller that's doing something weird. This is not usual FRC or flicker but something different
OxygenOS 13, HW overlays disabled, same experience with both the 60hz and adaptive 90-120hz modes
DisplaysShouldNotBeTVs what phones don't give you any symptoms just the Redmi 3 or? I've tried so many phones lately and all are brutal sadly. Next one is gonna be the cat s62 pro I'm gonna test soon
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Thanks for the insights. Most likely we have different sensitivities and I agree about the weirdness and blurriness to it. I just turned on my old redmi note 6 pro which was being "borrowed". The redmi note 6 still feels superior to the N30 edit: in terms of text rendering but I see visible gray flicker when filmed with the n30 slow motion mode. The note 6 is still running android 9 and MIUI 12.01Stable.
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DisplaysShouldNotBeTVs After using the N30 for just 20-30 minutes I feel extremely tired to the point I want to fall asleep
I have noticed this with another person looking at my phone just yesterday. He didn't attribute it to the phone but just said he wanted to go to sleep afterwards. Then this is also the unit variance in panels etc. How is your iPhone 14 Pro?
It's the software, GPU or panel controller that's doing something weird. This is not usual FRC or flicker but something different
Also, just the PWM waveform itself looks complex (multiple frequencies) and has greater depth not like the other phones (redmi note 6, moto g7)
Nord N30 PWM at 5uS time window showing 71.7 kHz flicker and the weird overall shape
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