I wonder if 1703, 1709 or 1803 could be better than 1809. I remember seeing some update notes about 1809 adding dithering control for apps
Lenovo T480 - Yes, Win10 1809 downgrade *matters* just like others say here
- Edited
jordan From what I've read, it seems like many here had issues with all of those other earlier "post-Creators Update" versions of Win10, but specifically 1809 worked fine for them -- this is why I went with 1809
Main flaw with this screen so far is noticeable PWM, and that it's too dim at max brightness, even compared to other screens I already call dim. It's only 250 nits. I'm pretty sure that my old Yoga which has a bright enough but not overly bright screen is 300 nits.
Win10 1809 remains MUCH better than Win11.
Most things do in fact look stable on 1809, but even though I seem to have resolved the really bad dithering strain, I do feel like I'm still experiencing some PWM strain though.
(The way I can tell apart PWM strain is times where I still get eye strain even when the screen is perfectly readable, nothing feels shimmery, etc. I know it's PWM strain when I have "no concentration or reading symptoms, no sharp pain, but still feel ongoing pressure on the eyes" basically)
Here's hoping that the panel in the other T480s I'll be trying soon has less or no PWM
- Edited
You can relatively easily replace panels if you want. I'll add your current panel to my list.
https://ledstrain.org/d/2589-products-to-try-or-avoid-pwm-flicker-and-temporal-dithering-testing/271
Your observations make sense. I had no eyestrain problems with the T480s even with the non-hdr matte WQHD panel when I bought it brand new when it was first released running on the older windows 10.
Hopefully sooner than later I can test the N140HCG-GQ2
If you get a T480 the comes with a FHD touch display, it will greatly limit your options as to what panels can be swapped out without tinkering with eDP pinout adapters and motherboard to panel cables.
- Edited
Used PWMHelper.exe to determine the PWM rate of this display, it is 990 Hz LOL. So much for "T480 is PWM-free" that I see endlessly repeated online…
PWM is definitely a significant issue on this 250nits Innolux panel. Even though I've gotten software output stable and I can now read complex information dense webpages etc. pretty smoothly on this display, I still end up with lots of strain behind eyes afterwards
Basically, Windows itself on 1809 is finally crisp, in focus, and mostly flat — but I still get the classic PWM eye pain.
Going back to my trusty Lenovo Yoga 13 2012 the pain entirely goes away. So despite the surprising progress I was able to make on the software and rendering side of things, there is still definitely a hardware issue with a poor quality panel and PWM here.
(My Yoga does have PWM too at all brightness levels according to my camera but at a much more subtle flicker depth. Also PWMHelper says "0" but I'm pretty sure it's just not able to read such an old Ivy Bridge Intel chip. I am pretty sure though that brightness control is also handled by Intel on the Yoga, because ages ago when installing some 2016-era Ubuntu I remember dealing with something like an "Intel PWM" driver to get backlight working)
Waiting to recieve T480S and potentially try a second T480 with a different random panel/possibly earlier BIOS version too before I decide whether to just return, or to e.g. keep one of them but swap the panel.
What's good though is that I'm optimistic about the software side now because of 1809. That has given me a lot more hope that swapping out panels is actually a viable solution and that I won't just end up with "the same dithering etc. but on different panels"!
- Edited
By the way, looks like PWMHelper.exe set function is actually supported by the T480 / 8th gen UHD 620! I was able to change the frequency from 990 Hz to 2000 Hz…
It seems to have successfully understood the command, as it flashed to a black screen and back
I definitely feel an improvement
Edit: Yep, I think it's doing something, as if I have brightness really low and toggle between 990 and 2000, I actually see a slight shift in backlight intensity
It is news to me that methods like these can still work to at least some degree on some "modern" Intel laptops!
For T480s with WQHD (B140QAN02.3 or LP140QH2-SPB1)
Opple PWM results: 0.0171 Flicker Index, 8.97% Modulation, 36342Hz at 52% brightness
- Edited
photon78s Yep, just proven again that specifically Win10 1809 matters. Newer Windows 10 versions are also just as bad as Windows 11 on these laptops
Received the T480, ordered a 1080p FHD based on listing but actually received one with the same LG 1440p panel you mentioned instead, so will probably be returning as text is too small when unscaled. Also this T480s has a much worse keyboard than the T480 I've been trying, probably just keyboard lottery
This panel also has PWM, also still there at max brightness even in BIOS and Ubuntu live USB. I'm still very perplexed why no one seems to mention that PWM happens at max brightness, I only ever see posts about "PWM up to 99%" or a lower number but I KEEP encountering panels that still flicker very obviously at max in a slow motion video
I thought you said yours didn't have PWM at max?
Arrived with Windows 10 22H2 this time, not 11. Didn't actually come with any display drivers installed yet lol (so remnants of newer graphics driver configuration files are not a factor). Installed 2017 driver, applied my usual methods
On 10 22H2, immediately got tons of strain, false 3D effect, tiredness, almost thought it was just the PWM at first since at this point I still thought Windows 10 was safe due to having a decent experience with 22H2 on Surface Pro 4
Finally downgraded to 1809, reinstalled same 2017 drivers as I did on 22H2…
And boom, strain on this LG panel is dramatically reduced yet again. Literally went from hating this to now strongly preferring the feel on my eyes of this panel (aside from the 2K resolution which is a dealbreaker) over the T480's very rough feeling 250 nits Innolux panel. 300 nits is such an improvement over 250 too
I might end up seeking out a 1080p LG panel to try now, compared to just half a day ago when I was about to rule out LG panels entirely, hopefully their FHD panels feel similar/better to how this one is feeling now on 1809
FWIW, this is one of the first times I've used 2K at 100% scaling and at least can tolerate the text size and still feel like I can read most text, which actually says a lot about how much this improved the panel. I have to lean closer than usual but now it's super crisp on 1809 compared to the fuzzy distorted mess it was on Windows 10 22H2
Even though text is super small on here which is uncomfortable in its own way, many apps I use are not compatible with scaling, I'm actually not feeling much strain on this T480s anymore despite the PWM (it's about half of the flicker modulation depth of the T480's Innolux, I guess within tolerable range for me. Still wish it didn't have PWM. What are the actually PWM-free T480/s panels?)
Total night and day difference compared to Windows 10 22H2 (which felt just as bad as Windows 11 did on the T480). That extremely disorienting false 3D effect on modern Windows versions, again, is very much eliminated after downgrading to 1809. I even have tested some of the same wallpapers and photos that were generating very strange false 3D and "distortion of perspective" effects on 10 22H2, and they finally look "normal" again on 10 1809
Still not sure why the Surface Pro 4 is "fine enough" on 22H2 with a generally flat image. It's either due to the older Intel HD 515 graphics instead of UHD 620, or it's just that I've never felt how much better it could be on an earlier verison. I still don't really see much false 3D effect on it though anyway which is unique, given that both T480 and T480s have 100x worse strain on these modern Windows 10 and 11 versions but totally flip around on 1809
BTW, the first T480 I bought is in great condition, but the PWM on its Innolux screen is too much for me. I can actually see it sometimes and constantly feel a strong PWM-type pressure in eyes while looking at it. After I try to at least get my hands on a 1080p T480s (can't panel swap on something I'm going to return, the keyboard and Elan trackpad on this T480s sucks anyway compared to the perfect ones on the T480 I'm trying), I might end up either trying to seek out a better T480s since I prefer the weight/thickness or possibly just keep the non-S T480 but do a panel swap
I need a 1080p panel, QHD does not work for me because I require being able to rely on 100% scaling at a more reasonable size for a good chunk of my work. Text with font smoothing turned off (pixelated) also looks a lot better at 100% scaling
- Edited
That's interesting with the panel differences. I don't see remember seeing flicker with slow motion video test at 240 fps but maybe your iPhone slow motion camera picks things up that my s10+ does not. I also didn't see "pwm lines" using high shutter speed camera (1/24000 sec). The opple results are what they are for a cheap measurement device like that. I think PWM or some kind of minute variations in output is still present in more devices that we think simply due to the limitations of measurement. I did not test using the ThorLabs photodetector device for oscilloscope as I acquired that after doing all the initial testing. Unfortunately, I no longer have that LG panel for retesting as I replaced it for the B140 (also WQHD) one due to it have less pixel flicker in my testing. I gave that T480s to a family member who uses it without problems so I'm waiting on a regular T480 for testing panels. Panel purchases is unfortunately hit or miss so it might be a while before I actually get the model I intended. I wish their were more options in the laptop world where you can still do these kind of diy changes. I have thought about getting a frame.work mainboard and building my own "frankentop" but life is too short for that kind of diy work right now.
One random thing I've noticed with the thorlabs device with oscilloscope is that flicker waveform increases the higher the brightness setting on the LG 27gp95r-b external monitor. Perhaps I'm picking up something else other than flicker.… Need more verification on this observation.
- Edited
photon78s maybe your iPhone slow motion camera picks things up that my s10+ does not
Interesting… overall, you won't see the flicker on white backgrounds, but if you open up lcdTech Dynamic Range Test website and film the color strips at 240hz, or film the background on https://monkeytype.com/ (a site someone else was using to detect flicker on M1/M2 Airs), you will see flicker even at 100% brightness
It's not dithering because I have some other devices that have obvious FRC I can see through my eyes but is fine grained enough to not be picked up on camera, like an old 6bit+2FRC TN monitor I have that completely stops PWM at 100% (but has terrible PWM anywhere under that, LOL)
This leads me to believe that the flicker I'm detecting is still PWM or something else adjacent to the backlight.
I know that a lot of Android cameras have "anti-banding" features that are set or forced to on (not related to color banding, but related to those darker PWM bands in recordings) to smooth out any flicker from lightbulbs/screens from a recording, I suspect that the iPhone camera app disables its equivalent whenever in slow motion mode but not sure if Android camera apps do the same
As I mentioned before, the medium gray background in the BIOS also triggers it too (although the BIOS does run at 50% brightness, so it's not as useful for the whole 100% brightness situation)
Is there anything I should test on my LG 1440p T480s before I return it? I do not have any actual microscope or light meter FYI
- Edited
I will test using your suggestions when my N140HCG-GQ2 arrives but it's another Innolux panel. So far, I've only tested those two wqhd panels and R140NWF5 R6 which has PWM lines in high speed shutter photos visible with the android phone camera. I forgot about anti-banding features and rolling electronic shutter! Since anti-banding is a potential problem I will focus mainly on oscilloscope measurements going forward.
My goal is to find a panel with PWM similar or better than the result from my 7i.
https://ledstrain.org/d/2589-products-to-try-or-avoid-pwm-flicker-and-temporal-dithering-testing/281
- Edited
photon78s Alright, the main thing that matters to me is only that there is no PWM at max brightness (since I almost always run 300 nits screens at 100% brightness anyway).
Using any old iPhone 5s or later I'm pretty sure that flicker can be detected on those two websites I mentioned earlier (in Firefox, to avoid Chrome's dithering on the banding test) while filiming in the iOS slow motion mode. I can see it at both 120hz and 240hz camera settings, I typically use 240hz. It's not Firefox causing it because it also shows up in a screenshot of those pages loaded into MS Paint.
Simply filming those sites at 100% brightness is what I do on my 14 Pro or SE 2020 and it's very obvious that the gradients/backgrounds on those sites are flickering. White backgrounds won't actually indicate PWM on most cameras as that's when the cameras are more likely to filter it out, which is why I use gray instead.
- Edited
Just for reference, here is my lenovo 7i at 100% brightness showing the monkeytype.com gray background filmed with s10+ at 240fps and played back at normal speed. Unedited straight out of the default camera app. I see a lot of camera noise.
- Edited
photon78s Interesting, I see a faint line at 0:18 moving from the top to bottom similar to a PWM scanning pattern, a few times in some other points in the video as well, I wonder if your camera is filtering it out
For me, I get a lot of camera noise on all screens, but I either see
- nothing at all except noise, indicating no PWM at max (MacBook Pro 2016 and M2 Touch Bar 2022 where I can't detect it at any level, and two Samsung TN monitors that are only stable at 100% but otherwise show obvious PWM anywhere else under that)
- very thin lines that indicate high frequency (Surface Pro 4)
- or, the entire background is constantly flashing slightly darker and brighter very obviously (pretty much every other laptop I've tested, even my favorite reliable Yoga 13 2012)
I've never seen "a line that moves down but then goes away" like I can spot in that recording
it seems like anyone who has a camera that was capable of detecting the PWM on the M2 Air (which were originally mistaken to be PWM free before some others and I each tested multiple models of M2 Airs) also has a good chance of being able to detect PWM at max brightness on other laptops too
- Edited
What shutter speed and other settings are you using in your filming for testing replication purposes and perhaps seeing some videos.
- Edited
photon78s What shutter speed and other settings are you using in your filming for testing replication purposes
Basically the default iPhone 14 Pro camera app on iOS 16.4.1, slow motion, 1080p 240hz, 1x zoom, slightly lower exposure after focusing in order to get the colors on the screen to look like what I see. No changes to shutter speed as the default camera app doesn't have any setting for that. I also sometimes need to lightly clean all the lenses including the LIDAR sensor before filming as the lenses on this phone frequently get super dirty and wash out the image lol
Sometimes I can even see the flicker in the slow mo view finder before tapping record. But it goes away in photo and video mode. This implies that any internal anti banding feature probably gets turned off in general by iOS in slow motion mode. It's also ideal to turn off all light bulbs in whatever room you're in too, just sunlight, to rule out any other flicker.
In settings I have view outside frame unchecked, prioritize faster shooting checked, lens correction unchecked, macro control checked if that matters
I've also been able to get basically the same results filming with an iPhone SE 2020 on iOS 17.2.1. So probably many iPhones will work.
- Edited
Have you tried installing Linux on your SSD on your T480? How did it compare to Windows 10? I'm interested in trying a T480. Several people here seem to have had good experiences with Thinkpad T480 and X280, and a forum member in another thread said "Lenovo's P5x and P15 were the best laptops on my eyes ever".
- Edited
Update:
Even though I was able to """kinda""" improve the Innolux N140HCA-EAB enough where I could "at least look at it", the Innolux still sucked, generally super strainy, really weird and obvious color and oversharpening anomalies, and much more intense false 3D effect compared to my good devices.
Today I just swapped out the 2016 Innolux panel for a 2014 LG LP140WF3-SPD1 (LGD046D). Luckily was available from a smaller eBay seller as "open-box old stock", so I knew I would receive the exact panel and not some "compatible" one.
Both are 1080p 6-bit, although the LG is brighter and has more sRGB coverage. Was inspired by this post which claimed that they could "stare at it for hours and hours without getting sore eyes or a headache"… so definitely wanted to try
first impressions
Day one impressions: at the very least, I am never touching Innolux again LOL
At least when compared to the Innolux, the LG is a breath of fresh air… Brightness level is great. No more "immediate" eye pressure and headache. The screen doesn't feel like it "bulges out in the center" like the Innolux did. Whites are less yellow, and I notice that I can read text from farther away. Matte coating is WAY better, I could tell even before I installed it. However, too early to determine if it's safe.
This 2014 LG is also definitely better than a newer LG 1440p that came with a T480s I tried, definitely seems to be flatter and no "instant disorientation" like that one caused.
Note that the LP140WF3-SPD1 was apparently manufactured in both glossy and matte versions according to some Reddit posts. Mine is matte
has mild flicker, but my "safe" screen does too
- The LG does have mild ("tiny brightness dip" style, non-strobe) PWM and I can see some pixel inversion, but my "perfect" panel (LP133WD2-SLB1 from 2012) also has this. The PWM looks like the same intensity on camera. I don't see any "erratic" temporal dithering on either LG after launching ditherig.exe -- just pixel inversion. At least on my trusty SLB1, these have never affected my eyestrain or productivity, so I'm not worried about this part.
For reference, the bad Innolux panel has similar brightness dips, but that one sucks whereas my "reference" SLB1 is fine. If I only had the Innolux, I would probably think that flicker was the issue… but I have a safe screen with the same flicker, so I can rule that out. (On the other hand, "strobe-style" PWM definitely messes with me)
no verdict until i fully test
Will need to put this LG through a full week of testing before I make any claims. I already know that I'm 100% avoiding Innolux, even their higher end panels (this is why).
Will do some in depth comparison with a bunch of test images on both my safe 2012 SLB1 and this 2014 SPD1. I will post later about any specific differences I notice (aside from the obvious ones like wider color gamut). Seems to be less difference between Windows 10 and the VM now, but can't say for certain yet. Still on 1809
Definitely regret contributing to the infamous "usable panel turned out to be bad" problem here with some of my earlier posts about the Innolux. I've learned, will be more considerate in the future.
Currently, the 13-inch 2012 LP133WD2-SLB1 is still the ONLY laptop+desktop display, even considering CCFL monitors, that I can 100% say with certainty is safe -- i.e. easy to read AND does not cause eye strain.
(It's also a total mystery, as that 2012 screen is so uniquely good despite its mild flicker and WLED backlight.)
However, first impressions of the LP140WF3-SPD1 seem OK. I wrote this post on here and unlike the Innolux I don't have a headache afterwards.
The real test though is how it stacks up against my single "truly good" panel. I'll update a week from now. Cautiously optimistic
- Edited
DisplaysShouldNotBeTVs one thing I'm liking about this new LG screen is that it feels like my eyes can relax by "looking past it" -- despite it being matte instead of glossy -- this reduces strain because it doesn't feel like it's a harsh brick wall that "stops my eyes" at it
Pleasantly surprised by this. Originally I thought this feeling was only possible with glossy screens (because it seemed to be connected to looking at the reflection), but this indicates it's possibly more about the pixels themselves
(cc @async)
On the other hand, the prior Innolux was absolutely horrible with this. In addition, multiple devices with AUO panels, even an old panel in a 2013 tablet that's "OK enough where historically I was decently productive on it", fail this test and cause strain when my eyes do this. I associate AUO panels with "consciously having to avoid relaxing my eyes", even if text readability is OK
Therefore, older LG IPS seems to at least have the "most potential". After all my "safe" laptop uses LG IPS. I really believe that somewhere there is another panel like that
Again no verdict at all yet, but generally better first impressions compared to other screens I've tried!
- Edited
Instead of changing displays I would buy a used T590. They are cheap nowadays and they REALLY are pwm free.
And concerning Windows 10: You can easily update to 21H2 without experiencing any dithering.