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asleep

macrumors 68040
Sep 26, 2007
3,773
1,631
Well that’s about as glowingly positive across all aspects as the most optimistic applefan could have hoped for.

93% rating puts the iPad Pro 11 M4 back atop the tablet group.

IMG_5457.jpeg
 
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geoelectric

macrumors 6502
May 19, 2008
376
66
240Hz worst case PWM actually seems pretty good for an OLED display. Most other handheld or laptop sized OLED devices for which I looked up PWM were more like 60Hz worst case.

Their best case and average case numbers are heavily skewed by LCD backlighting, which is typically up in the 4-5 digit frequencies. They really should separate those statistics out by tech.
 

Sheepish-Lord

macrumors 68030
Original poster
Oct 13, 2021
2,528
5,145
240Hz worst case PWM actually seems pretty good for an OLED display. Most other handheld or laptop sized OLED devices for which I looked up PWM were more like 60Hz worst case.

Their best case and average case numbers are heavily skewed by LCD backlighting, which is typically up in the 4-5 digit frequencies. They really should separate those statistics out by tech.
What I find unusual about the PWM is when you look at the iPhone Pro series. Either Notebookcheck changed their testing methods or the PWM got much worse after the 13 series:

13 Pro - 510Hz
14 Pro - 240Hz
15 Pro - 242Hz
-----------------
iPad Pro (2024) - 239.1Hz

I'm not sure why the tech potential got worse if the testing method stayed the same.
 

geoelectric

macrumors 6502
May 19, 2008
376
66
What I find unusual about the PWM is when you look at the iPhone Pro series. Either Notebookcheck changed their testing methods or the PWM got much worse after the 13 series:

13 Pro - 510Hz
14 Pro - 240Hz
15 Pro - 242Hz
-----------------
iPad Pro (2024) - 239.1Hz

I'm not sure why the tech potential got worse if the testing method stayed the same.
Those last three are probably within the margin of error. If the 13 was truly 510Hz *worst* case that’s pretty impressive. I think these newer models are 480Hz best case?
 

klasma

macrumors 604
Jun 8, 2017
7,440
20,730
What I find unusual about the PWM is when you look at the iPhone Pro series. Either Notebookcheck changed their testing methods or the PWM got much worse after the 13 series:

13 Pro - 510Hz
14 Pro - 240Hz
15 Pro - 242Hz
-----------------
iPad Pro (2024) - 239.1Hz

I'm not sure why the tech potential got worse if the testing method stayed the same.
The 12 Pro also measured around 240 Hz. It's the 13 Pro that is the outlier. Peak brightness was significantly increased on the 14 Pro, which may have necessitated returning to the lower frequencies.
 
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Sheepish-Lord

macrumors 68030
Original poster
Oct 13, 2021
2,528
5,145
The 12 Pro also measured around 240 Hz. It's the 13 Pro that is the outlier. Peak brightness was significantly increased on the 14 Pro, which may have necessitated returning to the lower frequencies.
Good catch! I compared the 13 Pro and 14 Pro, the 14 had much higher HDR and outdoor brightness so that must be it.
 

GMShadow

macrumors 68020
Jun 8, 2021
2,122
8,655
What I find unusual about the PWM is when you look at the iPhone Pro series. Either Notebookcheck changed their testing methods or the PWM got much worse after the 13 series:

13 Pro - 510Hz
14 Pro - 240Hz
15 Pro - 242Hz
-----------------
iPad Pro (2024) - 239.1Hz

I'm not sure why the tech potential got worse if the testing method stayed the same.

14 Pro and 15 Pro screens are different - the 12 and 13 Pro are 10-120hz refresh, the 14 Pro and up are 1-120hz refresh.
 

Sezel

macrumors member
Apr 11, 2024
36
31
What about the new iPad Air models, they seems to use the same display panel as before (no flicker due to PWM) but notebookcheck mentioned no flickering of any kind was present on the new iPad. It means the new iPad Air are without temporal dithering?
Below quotes are from their review of M1 and M2 iPad Air.

iPad Air M1 (2022)
https://www.notebookcheck.net/Apple-iPad-Air-5-2022-Review-Many-Yays-Few-Nays.610447.0.html
"On a very positive note, we found absolutely no evidence of PWM for brightness regulation. However, it seems like currently (iPadOS 16.5) Apple uses temporal dithering to increase the number of colors that can be shown (see slow motion 240fps video below)"

iPad Air M2 (2024)
https://www.notebookcheck.net/Apple...-tablet-with-an-identity-crisis.841801.0.html
"The iPad Air 6 doesn't use pulse width modulation to control its screen brightness and we also noted no evidence of high-frequency flickering in our measurements, which PWM-sensitive people will certainly appreciate—especially since the Pro models have switched to OLED technology."
 

Sheepish-Lord

macrumors 68030
Original poster
Oct 13, 2021
2,528
5,145
What about the new iPad Air models, they seems to use the same display panel as before (no flicker due to PWM) but notebookcheck mentioned no flickering of any kind was present on the new iPad. It means the new iPad Air are without temporal dithering?
Below quotes are from their review of M1 and M2 iPad Air.

iPad Air M1 (2022)
https://www.notebookcheck.net/Apple-iPad-Air-5-2022-Review-Many-Yays-Few-Nays.610447.0.html
"On a very positive note, we found absolutely no evidence of PWM for brightness regulation. However, it seems like currently (iPadOS 16.5) Apple uses temporal dithering to increase the number of colors that can be shown (see slow motion 240fps video below)"

iPad Air M2 (2024)
https://www.notebookcheck.net/Apple...-tablet-with-an-identity-crisis.841801.0.html
"The iPad Air 6 doesn't use pulse width modulation to control its screen brightness and we also noted no evidence of high-frequency flickering in our measurements, which PWM-sensitive people will certainly appreciate—especially since the Pro models have switched to OLED technology."
At that point at I would get a refurbished 11" Pro from Apple since those don't have PWM and are still superior to the Air models.
 
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Sezel

macrumors member
Apr 11, 2024
36
31
At that point at I would get a refurbished 11" Pro from Apple since those don't have PWM and are still superior to the Air models.
But M2 iPad Pro still uses temporal dithering

iPad Pro M2 (2022)
https://www.notebookcheck.net/Apple...boost-for-Apple-s-creative-tool.668660.0.html
"Compared to the predecessor, all specifications and measured values are nearly identical: the resolution is still 2,388 x 1,668, which corresponds to the standard for other high-quality tablets. No PWM was detected, but we found temporal dithering in the 240fps video of the subpixels (of a gray patch) - see video below."


However NotebookCheck didn't mention anything about temporal dithering on the M1 iPad Pro. May be someone can check and update us all.

iPad Pro M1 (2021)
https://www.notebookcheck.net/Apple...pple-tablet-sparks-the-M1-Turbo.545894.0.html
"The display can also operate at up to 120 Hz, allowing it to display content smoothly. Positively, Apple does not use pulse-width modulation (PWM) to regulate the display's brightness levels. Hence, you should not suffer from eye strain or headaches when using the iPad Pro 11 (2021) if you are PWM sensitive."


Using temporal dithering means Apple is not using true 10 bit display panel (on both air and pro models). Is the technology not there/feasible? Or they are cost cutting.

Also, does the OLED panels (including the new tandem display as well) use temporal dithering?
Or PWM is the only cons of OLED regarding eye safety.
 
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Abstract

macrumors Penryn
Dec 27, 2002
24,889
921
Location Location Location
I don’t understand the PWM frequency result. I get that minimum and 25% brightness tests couldn’t detect frequency because maybe the amplitude was too low (and unscalable to determine a result), but why isn’t the lowest brightness due to having the lowest frequency?

50% brightness: 546.56 Hz
75% brightness: 239.47 Hz
100$ brightness: 482.31 Hz


I thought the lowering of brightness was achieved by lowering the frequency (so that the screen is bright less often, per second)? That would mean 50% brightness would have the lowest frequency, while 100% brightness would have the highest.

Anyway, just curious. I don’t suffer from PWM effects, but I suspect my wife does. Her recent iPhones have been almost unusable for her until I set some screen setting trickery (as detailed on the internet somewhere).
 

klasma

macrumors 604
Jun 8, 2017
7,440
20,730
I don’t understand the PWM frequency result. I get that minimum and 25% brightness tests couldn’t detect frequency because maybe the amplitude was too low (and unscalable to determine a result), but why isn’t the lowest brightness due to having the lowest frequency?

50% brightness: 546.56 Hz
75% brightness: 239.47 Hz
100$ brightness: 482.31 Hz


I thought the lowering of brightness was achieved by lowering the frequency (so that the screen is bright less often, per second)? That would mean 50% brightness would have the lowest frequency, while 100% brightness would have the highest.

Anyway, just curious. I don’t suffer from PWM effects, but I suspect my wife does. Her recent iPhones have been almost unusable for her until I set some screen setting trickery (as detailed on the internet somewhere).
It could be related to the tandem OLED. The two layers may not always use the same frequency, and/or lower brightness levels may only have one layer active.
 

cjsuk

macrumors 6502a
Apr 30, 2024
616
2,262
What I find unusual about the PWM is when you look at the iPhone Pro series. Either Notebookcheck changed their testing methods or the PWM got much worse after the 13 series:

13 Pro - 510Hz
14 Pro - 240Hz
15 Pro - 242Hz
-----------------
iPad Pro (2024) - 239.1Hz

I'm not sure why the tech potential got worse if the testing method stayed the same.

Just checked them both. The methodology is the same and it looks correct. They don't say what sensor they use for the text and the oscilloscope they were using has changed (just upgraded to a later model) but the test scenario still stands.

The cones in your eyes have a total response time of around 20ms and at the worst 239Hz, that is 4.2ms so there's absolutely no chance you can perceive the difference between any of these. I wouldn't expect any perception at all being possible until around 8-10ms.

As for the difference between the display technology, OLEDs are PWM'ed otherwse the net power consumption is more than twice as much for the same visual response and the heat generation is off the scale.

I would worry more about the higher contrast causing eyestrain over time than the PWM myself.
 

TheRealAlex

macrumors 68030
Sep 2, 2015
2,982
2,248
I didn’t need to wait 2 weeks to figure this out. It’s the best Display I’ve ever used and seen period. Tándem OLED next to my 240hz OLED 15.6” Gaming Laptop.

 
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