Products to try or avoid? PWM Flicker and Temporal Dithering Testing
That's interesting as others here find it hard to tolerate modern iPhones. So the 12 PRO has PWM according to notebookcheck: https://www.notebookcheck.net/Apple-iPhone-12-Pro-Review-Powerful-Smartphone-with-Retro-Styling.504562.0.html
Not sure about temporal dithering. Perhaps other aspects of the display (smaller screen for instance) makes it comfortable. Hope the G15 continues to work for you!
I already posted a video here where you can see the flickering on win10 1809 in comparison with win10 21h1 (I don’t remember exactly)
So, lat week I experimented on my safe w10 1809, found the datasheet of the installed panel, and using CRU I increased the monitor refresh rate from the factory 60 Hz to 72 Hz (keeping in mind pixelclock limit searched in datasheet) with autosettings for other synchronization parameters. Then I felt that I couldn’t use the screen, or rather, I could, but after it I felt pain in my temples. This went on for 4 days and yesterday when I looked at the taskbar I saw the same "fast chaotic pixel movement". I set monitor back to 60Hz, but it didn't help. I set nvidia's output to fullrange, but that didn't help. ColorControl also demonstrated no-dithering.
Only a complete reset of EDID settings via CRU helped. After that, I saw that the taskbar has a “lazy slow standard flicker” and after another 1 day I get back my safe PC.
Any ideas?
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Edit: Nevermind, I think this is just circular polarization. See this post where Seagull mentioning using tracing paper to help with polarization effects.
https://ledstrain.org/d/2315-vertical-and-horizontal-polarization-as-eye-strain-trigger/4
Have you tested your screens by looking through polarized sunglasses? On my MBP TB, I can never get the screen to go fully black by rotating the sunglasses to a certain angle like 90 degrees like with the 7i and other displays.
Instead I get a blue-purple image here:
https://ibb.co/cQ5Yg5v
Right side is looking through the sunglasses rotated at 90 degrees which is the maximum I could get to dim the screen. So it looks like only certain wavelengths are polarized?
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photon78s Perhaps you were adapted to the default refresh rate
I can use another 165hz monitor without issues…
I change refresh rate in safe w10 1809 setup to "not registered" and got same noise (which gives me eye-strain) as in video with "bad" win versions I tested
Have a look -> https://filetransfer.io/data-package/iwnh2gOL
Only EDID reload (I think from monitor's eeprom) made reset to "default lazy flickering"
Can OS flickering be due to bad EDID interpretation? I can find thread there where guy desrcribe same feeling as mine when set non original framerate, but when I install all win versions above 1809, I get chaotic pixel movement equal I got setting non original framerate in "safe win version"
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I've read users observing thin white lines in between pixels on certain displays. I don't notice them on my 7i or MBP but I remember seeing them on an older model Ryzen Legion laptop (don't know the laptop model panel unit). This reviewer calls it a "rastering effect".
https://www.reddit.com/r/thinkpad/comments/qxxtoq/thinkpad_x13_gen_2_amd_initial_initial/
There is a display lottery, and I lost it. Mine has the InfoVision M133NW4J R3, and it’s really bad. Out of the box, it has a warm/reddish cast, though a calibrated color profile may help. It also has a weird rastering effect, where you can see faint lines between the rows of pixels when you get moderately close to the panel. Looking at it with a 20x loupe, it seems that the space between rows of pixels is slightly further apart than between columns.
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So I was interested in how light polarization might affect eyestrain and I tried some tracing paper in front my LG display. Looking through my polarized sunglasses I see no darkening effect however which why I orient the glasses. This means no more polarized light. The visibility is not too good for fine detailed work but passable only if you can get the paper fully pressed against the screen.
https://ledstrain.org/d/1421-tracing-paper
I found this research on smartphone light polarization (circular versus linear) on eye symptoms. Not sure about the conclusions of that paper but relevant to some observations on this forum. For myself, it seems that I'm not too sensitive (humans are supposed to be not sensitive at all to polarization?) to either type of polarization. Some iPhones are circularly polarized and so is my M2 MacBook Pro Touch Bar laptop.
Comparison of the influence of light between circularly polarized and linearly polarized smartphones on dry eye symptoms and asthenopia
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PSA Update!
My LG 27gp95r-b is showing fainting horizontal banding across the entire width of the screen. Still too early to say if this causes increased eyestrain as I have to be very close to the screen to see it so it went undetected during my several months of ownership so far. This is an ips UHD rez 144hz monitor with 8 bit + FRC dithering. Hopefully this is not a widespread QC issue.
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As some of you are considering trying older lenovo windows/linux laptops, I going to start a list here of potential replacement display panels for ThinkPad T480 and/or T480s that may work for some eyestrain wise.
- https://www.panelook.com/LM140LF1F02_Panda_14.0_LCM_overview_48911.html (144hz refresh rate for a thinkpad!)
- https://www.panelook.com/N140HCG-GQ2_Innolux_14.0_LCM_overview_41388.html (This is a low power IGZO FHD display for better battery life, IGZO means indium gallium zinc oxide as semiconductor material)
- https://www.panelook.com/R140NWF5_R6_IVO_14.0_LCM_overview_36125.html (matte FHD touch screen, 6 bit color so not recommended for dithering reduction)
- https://www.panelook.com/B140QAN02.0_AUO_14.0_LCM_overview_37246.html (hdr wqhd glossy)
- https://www.panelook.com/B140QAN02.3_AUO_14.0_LCM_overview_33893.html (Non-hdr wqhd matte, what I am using in T480s)
- https://www.panelook.com/LP140QH2-SPB1_LG%20Display_14.0_LCM_overview_40282.html (I prefer number 5 to this which came with my T480s)
- https://www.panelook.com/N140HCA-EAB_Innolux_14.0_LCM_parameter_30063.html (has PWM)
How to guide:
https://forum.thinkpads.com/viewtopic.php?t=127439
https://www.ristrettorambles.com/upgrading-settling-into-the-thinkpad-t480/
https://www.ifixit.com/Device/Lenovo_ThinkPad_T480
https://www.ifixit.com/Device/Lenovo_ThinkPad_T480s
One thing to note is whether your machine comes with 40 pin or 30 pin cable and the eDP version and number of lanes. You may also have to use a pinout converter with one compatible with your chosen panel. When I replaced the panel on the T480s, the cable length was a just barely enough to reach the location of the slot on the panel. Another aspect to check is if you are using narrow or regular pitch pins. 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.
Resources for understanding pinouts and cables:
https://www.reddit.com/r/thinkpad/comments/uw0tit/t480s_from_fhd_touch_to_non/
https://old.reddit.com/r/thinkpad/comments/up3bql/seeking_advice_for_p14s_screen/
https://www.reddit.com/r/thinkpad/comments/i9oqr1/comment/g4fm42k/?rdt=45559 (see 30-pin normal eDP cable FRU 01YR501)
https://www.reddit.com/r/thinkpad/comments/v8tf2n/t480_screen_buying_advice_in_eu/?rdt=53836
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It doesn't look to me to be vertical green lines but white lines or spaces between horizontal rows. See this:
Ignore the rainbow moire but notice the lines in the lighter parts in the trees. And this seems to be a static artifact. Panel degradation?