Products to try or avoid? PWM Flicker and Temporal Dithering Testing
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To emphasize, it should not at all affect the laptop's warranty. The warranty info on the ditherig site only means that the guy who wrote this software program does not offer warranty for his software.
About other "strong enough" laptops, check out this discussion with the Asus Strix laptops:
Some more curiosities:
Unlike my PCs, both the mac mini and the 13 inch MBP Touch Bar I've tested emit a strong wireless emf signal upon boot up and then the signal stops. I don't know how to disable this. It is not controllable from within Mac OS with the standard wifi or bluetooth settings.
The Ra color rendering index value is higher on the 7i than on the MBP TB (87.7 versus 71.5) as measured with spectrometer. Both have similar spectrums as expected for WLED backlight displays that are a far cry from natural sunlight spectrum.
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So I setup two crypto mining PCs both 7950x cpus BUT first PC is a asus x670e crosshair motherboard and second PC is a b650m edge MSI itx motherboard They are meant to be running headless (no screen) BUT when I enter bios and configure CPU settings and also short time booted in HiveOS(Linux mining OS) The x670e Asus makes me feel AWFUL.. the MSI b650m itx one didn't bother me like the asus. I now am a strong believer in motherboards causing issues... Same HDMI cord too and this was using the motherboards HDMI port with Ryzen 7950x iGPU. Feeling not so good right now. I've been tinkering with them the last 3 days mostly msi and just earlier I tweaked the asus more and just is BAD. I felt this a little the last few days when I used it but this time I used it longer and yikes not good..
It's basically the same feeling I got with the iPhone 11
Edit: this was connected to my old Samsung TV that I normally don't use
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So frustrating to add now motherboards as eyestrain contributor. You would think that boards supporting the same chip should be more consistent. At least you don't have to config those rigs often. Set it and forget it. Next time maybe you could run the iGPU output through a hdmi converter and OBS to get rid of the dithering on whatever computer you find most comfortable.
Don't laugh, I'm being serious unless you have food allergy.
https://www.quora.com/Is-chicken-liver-good-for-the-eyes
https://www.livescience.com/1021-scientists-eye-benefits-spinach.html
I need to find a good recipe.
Here is the spectrum for the 7i
https://ibb.co/7z6CvRv
and the "good" M2 MBP Touch Bar:
https://ibb.co/TKWmjyQ
Both are spikey but the red seems unbalanced on the Mac. Night light off and default settings on 7i. Mac is running sRGB color profile with true tone and night light off. Sunlight is a gentle curve with no big spikes.
Returned the pro 7i. bittersweet feeling. It’s such a quality laptop but after being without a a pc for a month now realizing how much it fucks with my mental and physical state just looking at a screen for a short while. it’s so sad.
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this is probably because you're running the sRGB profile, that is not the laptop's native color gamut.
P3 displays have the ability to create oversaturated reds (and blues) by design, running it in "sRGB mode" will just "stretch" normal sRGB red all the way out to maximum P3 red.
another thing that may affect this is panel variation, my first TB M2 had the classic "screen lottery greenish-Yellow Tint" (also often seen on iPhones) but my new one doesn't — it now has a very slight "reddish" tint instead which is nice because a lot of my other "most usable MacBooks" have a reddish tint!
each one actually had an entirely different color temperature to my eyes IMO. of course true tone was off on both
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13 inch M2 MacBook Pro Touch Bar testing:
I measure the same red peaking spectrum when on Color LCD profile. I measure on pure white like RGB (255, 255, 255). Not a concern for me. Being using this base model machine for the last few days and so far it feels comfortable and dare I say more comfortable than the 7i screen at 240 hz refresh rate even with all the dithering removal workarounds enabled.
So I used an industrial/scientific grade Thorlabs PDA100A2 photodetector and I see the threshold between almost flat signal to high frequency PWM or PWM like fluctuations at 63 to 64% brightness as adjusted using BetterDisplay display. Switching between 1280 and 1440 Rez didn't affect these readings.
What is strange is the notebookcheck reported 56% brightness threshold for PWM. Switching from 56% to 57% brightness sometimes but not always results in suddenly less high frequency peaks in the signal but it's not a consistent occurrence. Sometimes going from 57% to 58% higher brightness would increased not decrease PWM-like fluctuations. What is consistent on my cheap oscilloscope is the 63% to 64% brightness threshold change. Need to recover budget wise then someday will upgrade my oscilloscope. I use 20dB gain setting on the photodetector to account for lower backlight and the photodetector noise is still low as stated in the manual at 219 μV RMS and the bandwidth is 800kHz.
My general impression using this pro photodetector is that the Opple4 is still giving a roughly useful waveform and not just pure low light noise in my previous testing at 50% brightness. The Thorlabs device is awesome and should be. It cost almost as much as a used laptop!
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photon78s Unlike my PCs, both the mac mini and the 13 inch MBP Touch Bar I've tested emit a strong wireless emf signal upon boot up and then the signal stops.
strange, probably due to the newer generation of wifi in apple silicon macs? maybe Find My network/Activation Lock related? (it probably still runs similar code before booting the secure volume even if Find My is not set up)
this kind of radio related stuff doesn't seem to be an issue for me at all though, i don't feel anything "off" at all starting up the machine or rebooting. it just feels normal
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photon78s I see the threshold between almost flat signal to high frequency PWM or PWM like fluctuations at 63 to 64% brightness
yup this makes sense, lines up with what notebookcheck said
(even though notebookcheck can honestly be really inaccurate a lot of the time *cough cough saying that the M2 Air has no flicker at any brightness level even though it DOES at ALL levels*, they got essentially the same reading and similar brightness switching threshold here!)
photon78s Switching between 1280 and 1440 Rez didn't affect these readings.
this also checks out, the 63%-64% switching threshold between PWM and flat signal lines up with typical PWM backlight dimming techniques, nothing out of the ordinary here. it makes sense (and is a good sign) that screen content doesn't affect this
DisplaysShouldNotBeTVs strange, probably due to the newer generation of wifi in apple silicon macs? maybe Find My network/Activation Lock related? (it probably still runs similar code before booting the secure volume even if Find My is not set up)
this kind of radio related stuff doesn't seem to be an issue for me at all though, i don't feel anything "off" at all starting up the machine or rebooting. it just feels normal
I'm not going to debate if EMF is a biological issue or not, but the closest "cause and effect" relationship I've seen is EMI or internal "brownouts" of power rails has been linked to causing backlight flicker/ripple that isn't just normal PWM.
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Dadab12 What is the reason you are still trying to get Macbooks to work for you? just the MacOS or the ecosystem?
I build iOS apps, I work on projects with others in Logic Pro. CoreAudio is unmatched in extremely low latency audio on the go at extremely small buffer sizes straight out of the built-in headphone jack.
The precision of MacBook trackpads and diagonal scrolling that always works is essential for image editing and design work outdoors in places where I can't use a mouse. You can't start dragging a file, switch 2 desktops, scroll a window in both directions, Force Click into a folder without waiting, and drop the file ALL in one single drag gesture on even the best PC trackpad — and even though it might not sound like it, that's something I actually do dozens of times per day. (This is why an actual usable MacBook is ideal for me instead of a Hackintosh laptop)
Much better built-in apps that I actually use, Preview is essential, nothing really comes close for quick and seamless editing/splicing/markup of PDFs. Generally more ergonomic keyboard shortcuts in most apps. COLUMN BROWSING VIEW IN FINDER.
Seamless UNIX terminal environment available at the same time as access to commercial apps like Adobe (unlike Linux) without quirks and hacky workarounds (unlike WSL2).
Due to all of this, even my usable Windows laptop I simply use as a screen sharing client into a Mac most of the time lol.
photon78s the Opple4 is still giving a roughly useful waveform and not just pure low light noise in my previous testing at 50% brightness
Great findings! Brightness adjust was not linear for my last 2 laptops (at 80% it looks like 60% in my old laptop, according to Opple4 brightness measurments)
You talked about 50% threshold for Opple4, could you say brightness values (min, max, avg) - if I get data above it, will say "my opple4 show display noise, not its own"?
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I was not able to get the Opple4 to reliable distinguish PWM between 64% and 63% like I can with the Thorlabs device. As I increase brightness, the Opple waveform decreases in thickness until about 95% brightness or above 400 nits of brightness so I think the Opple is very noisy.
Edit: Repeating Opple measurements might yield slightly thicker or thinner waveforms even when the actual signal should be stable. The device seems suitable for checking larger fluctuations.
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16 inch Lenovo Legion Pro 7i 2023 laptop testing:
Using PDA100A2 photodetector, the switch between PWM-like display backlight fluctuations and relative flat line is at 85-86% brightness as adjusted in Windows 11. Overall, the 7i backlight fluctuations are less than those of the M2 MBP TB as I needed to set the photodetector gain to 50dB to notice these tiny levels of flicker. On the MBP, I only needed 20dB gain.