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There are no intermediate refresh rates between 48Hz and 120Hz in the Adaptive motion mode — it’s only one or the other. So, if you don’t use your phone very often in brighter conditions, the Galaxy S22 will mostly be running in its 120 Hz mode, constantly draining a bit more extra power. For why Samsung has set it up this way, the main reason is to avoid color shifting when the display switches between refresh rate modes. As seen on other phones — like the Pixel 6, Pixel 4 (XL), or OnePlus 8 Pro — the color temperature and gamma can abruptly change when interacting with the screen to and from its idle state. Things get problematic in lower brightness conditions since electrical non-linearities are exacerbated at low signal levels, and dim ambient lighting makes them more perceptible. Samsung decided to just avoid dealing with this as much as possible, leaving the screen mostly at 120Hz, and only allowing it to go to 48Hz in conditions where the shift can absolutely not be noticed — when things are bright.

Samsung also places refresh rate constraints on their LTPO panels, but they’re much less restrictive since the backplane has higher color stability when changing the pixel charge timings. Instead, Samsung limits its LTPO variable refresh rate only when the ambient brightness dips below 40 lux, rather than 200 lux.

Power vs Refresh Rate for Galaxy S22 Plus

But how much power does the screen actually save when it shifts down? In testing this, I measured total device power displaying a fullscreen dark-gray pattern at the minimum brightness allowed for the display to enter 48Hz, and I used a flashlight on the ambient light sensor to bypass the 200 lux limitation. This was repeated with the flashlight turned off to measure 120Hz power. My Lupin flicker meter was also actively reading the display to make sure the refresh rate was correct and constant; if I used a black pattern, I wouldn’t be able to verify the refresh rate, and the display driver may undergo other optimizations under the hood.

As the result, I measured an average reduction of about 150 mW in device power from 120Hz to 48Hz, which is definitely non-negligible. Having this reduction at normal-to-low brightness would improve battery life considerably, so it makes sense why other companies gamble with potential color shifts. From my testing, I couldn’t detect any color shift at the brightness constraint that Samsung has set for the Galaxy S22 Plus. Although it means that their constraint is working, I do think they could have allowed for a higher tolerance for some color shifting to reduce power (though it varies panel-to-panel).

Pulse-width Modulation

Almost every OLED on a phone uses pulse-width modulation (PWM) to adjust screen brightness. This method rapidly flickers the pixels on-and-off at a speed our eyes shouldn’t notice, so that we instead interpret it as a modulation of the screen’s apparent brightness. Using PWM is the best way to maintain the display picture quality when dimming a display, but some users can be sensitive to the flickering and may subconsciously notice it. For this reason, a higher PWM frequency is generally preferred to reduce the chance that flickering is noticed.

For those that are sensitive to PWM, Samsung hasn’t done anything to alleviate it. The Galaxy S22 Plus still flickers at around 240Hz, which is the same rate it’s always used. The modulation amplitude is also still pretty high, which contributes most to what people are sensitive to. If necessary, you can use Android 12’s Extra dim feature to lower the screen brightness with less intense screen flicker. One more interesting tidbit is that the screen’s PWM frequency changes from 240Hz to 192Hz when ramping down to 48Hz, which is done to keep the refresh rate as a common denominator of the PWM frequency.

Contrast & Tone Mapping

Tone Response for Galaxy S22 Plus (Natural, Medium brightness)

Min. Brightness Low Brightness Medium Brightness High Brightness Max Brightness Vision Booster

Natural Vivid

For the first time since the Galaxy S9, Samsung has landed a meaningful calibration change with the Galaxy S22 series. In the time being, the company had been one of the worst OEMs when it came to screen tone response, which lead to suboptimal content legibility in certain scenarios. More specifically, Samsung tunnel-visioned a display gamma of 2.2 for every brightness level, which is only appropriate for around 100 nits with minor screen glare. At low brightness, a straight gamma of 2.2 yields too much contrast and results in black clipping, which Samsung’s phones have been somewhat notorious for. In brighter conditions, a 2.2 gamma isn’t light enough to overcome screen glare. This year’s Galaxy flagships address both of these.

Samsung’s new tone mapping efforts are all part of what the company is calling Vision Booster. While the software service itself is only triggered under direct sunlight, there was a clear focus on applying its principles to other aspects of the display calibration. The ultimate goal is to adapt the screen contrast appropriately to its brightness and to the surroundings so that everything (shadows, mid-tones, and highlights) stays visible and in proper proportions.

Starting with the base target, the tone response that Samsung is aiming for its Snapdragon variants still seems to be a gamma of 2.20. In the past, Samsung targeted the sRGB tone response curve rather than gamma 2.20 for its Exynos variants, but I do not own an Exynos unit to verify if they’re still doing this.

Measuring the S22 Plus display, it comes out closer to 2.1, but this is likely due to too much green energy at low signal levels, tinting shadows slightly green. I’m not sure if the lifted shadows are intended by Samsung, but if it is, I welcome it. I uphold that the benefits of lighter shadows greatly outweigh the punchiness of a steeper picture when it comes to phones screens. When all shadow details are visible, viewing content on your phone becomes much more comfortable. Most of the time this is a matter of tone mapping (contrast) rather than screen brightness, and many phones in the past have struggled with content visibility at low brightness, including Samsung’s phones.

On the new Galaxy S22 Plus, there is now a strong boost to the shadows and mid-tones as the phone approaches minimum brightness. Compared to the Galaxy S21 Ultra, which used a straight 2.2 gamma at minimum brightness, nighttime viewing on the Galaxy S22 series has improved drastically. Furthermore, there isn’t any black clipping to be seen, and only the first 8-bit step is crushed when Extra dim is set to half-intensity. Good job, Samsung.

There’s a test I call the “minimum-brightness video feed visibility test” (rolls right off the tongue doesn’t it?), which consists of me scrolling down my Reddit or Twitter feed at minimum display brightness at night; if a video begins to play and it requires me to increase the display brightness to comfortably view it, then the phone fails that test. Proper display tone mapping shouldn’t require any increase in display brightness in low light, especially if your eyes have been dark-adapted. The Galaxy S22 Plus is the first Samsung phone I’ve owned to not miserably fail this test. For what it’s worth, the OPPO Find X3 Pro is still the king for night-time viewing: it has a feature to automatically lower the minimum brightness in low light, and it does this without introducing any black clipping, likely due to its true 10-bit panel.

Vision Booster sets pixel brightness into overdrive. Left: Vision Booster disabled; Right: Vision Booster enabled

Not only has nighttime viewing been improved, but so has daytime viewing. Under direct sunlight, Samsung’s Vision Booster service activates, which pumps up color lightness as much as the OLED is capable of. It’s basically a pixel overdrive setting on top of high brightness mode — it’s high lightness mode, if you will.

However, there are some downsides to it. One drawback is that it introduces a ton of posterization since the software uses a low-resolution histogram map to calculate what regions of the display to boost. It also doesn’t seem to function when the Eye comfort shield feature is enabled or set to “Adaptive”, which is a shame since both are features I enjoy. Vision Booster also only activates above 50,000 lux, which requires a direct path between the sun and your screen, and it turns off once the phone detects it is under 20,000 lux. It would be nice if Samsung could tweak Vision Booster to enable somewhere around 2,000 lux instead, and to vary its intensity as ambient brightness increases.

This brings me to the only negative thing about Samsung’s tone mapping, and it’s when the display hits its peak brightness without Vision Booster enabled. This occurs between 2,000 and 50,000 lux. In this state, the phone enters its high brightness mode, but it varies the brightness of white depending on the content APL. For low-to-medium APLs, the display gamma measures around 2.4, which is steep, and it impacts the visibility of shadow details when there’s screen glare. In comparison, when Vision Booster is enabled, the display gamma measures around 1.6. This issue is one of the biggest problems with all of Samsung’s displays, and it was so close to getting it all right with the Galaxy S22. Maybe next year.

One more thing: Galaxy phones are still the only flagship displays to incur color banding when displaying gradients, even with 10-bit content. The rotating gradients above should appear perfectly smooth, but they never have on Galaxy phones. I’m not sure why Samsung doesn’t just dither their media playback, but it’s an issue that shouldn’t exist in 2022 — every other OEM already got the memo.

White Balance & Grayscale Precision

Grayscale precision for Galaxy S22 Plus (Natural, Medium brightness)

Min. Brightness Low Brightness Medium Brightness High Brightness Max Brightness Vision Booster

NaturalVivid

As standard for sRGB, the Natural mode targets a white point of D65, which has an approximate color temperature of 6500 K. My measurements verify that the Galaxy S22 Plus measures a white point extremely close to D65. But even though my tools report an accurate value, whites still appear tinted green on the Galaxy S22 Plus OLED when compared to the standard spectral makeup for D65. This is due to the narrow spectral power distribution of OLEDs, and it’s a known issue that plagues all OLEDs. For this reason, an offset towards magenta is needed for the white point of OLEDs to perceptually match the standard. Sadly, Samsung doesn’t provide white point color adjustments within Natural mode, only Vivid mode, even though it’s more important for the Natural mode to have this type of flexibility.

Regardless of the targeted white point, an ideal display will maintain its color temperature independent of screen brightness or tone level. In this aspect, the Galaxy S22 Plus performs very well, although it still slightly trails behind panels that use an LTPO backplane. Dark grays below 10% tone intensity measure slightly yellow-green, though it’s definitely not that noticeable. Color tinting is also well-controlled at minimum brightness, and dark mode interfaces have clear separation and consistent coloring. And whether the display is at low brightness, medium brightness, or at max brightness, the white balance remains consistent.

Some phones experience shifts in color tint when the display switches between refresh rates, but I haven’t noticed any of that with my time with the Galaxy S22 Plus. This usually occurs in phones that don’t use an LTPO display backplane, but Samsung gets around it on the Galaxy S22 by being strict about when the phone is allowed to lower its refresh rate. As I’ve covered earlier, the refresh rate will only ramp down if the system brightness is above 33% and if the ambient brightness is above 200 lux. In doing so, Samsung ensures that problematic color shifts won’t be noticed, though this foregoes potential battery gains.

Color Accuracy

sRGB color accuracy for Galaxy S22 Plus (Natural, Medium brightness)

Min. Brightness Low Brightness Medium Brightness High Brightness Max Brightness + Vision Booster

sRGB P3D65

Both sRGB and P3 color accuracy on the Galaxy S22 Plus is just fine in Natural mode. Any color difference isn’t noticeable unless when critically looking for it; even the largest errors at blue weren’t noticeable to me comparing side-by-side to a reference (though this is probably due to color difference metrics being least reliable for blue colors).

As covered, the white balance measures bang-on to D65 at every brightness level, which is necessary for accurate color. The average and max color errors aren’t the lowest around, but to my eyes, the Galaxy S22 Plus display is just short of being reference-level — if only the white balance was correctable to counter metameric failure.

What’s impressive is that color accuracy remains decent when Vision Booster kicks in. Although it significantly raises color lightness and system gamma becomes dynamic, the screen’s relative saturation and color hue are maintained. When a lot of screen glare is present, some gamut compression occurs, so an increase in saturation is needed to combat it.

HDR10 Playback

Almost every new title released on streaming platforms nowadays is mastered for HDR, so it’s now very relevant to scrutinize the HDR performance on flagship phones. But, with the Galaxy S22 Plus, there’s not really anything for me to scrutinize. These HDR10 measurements are so textbook that I needed to re-do these measurements several times to make sure it wasn’t a fluke. Nope, they’re correct — they’re the best that I’ve measured on any display out-of-the-box. There’s definitely some variance in the color temperature for white, but just look at that color accuracy chart! It’s stupidly accurate. The ST.2084 tone reproduction is almost solidly through the dashed target, I probably wouldn’t be able to trace it any straighter by hand.

Backed by the brightest screen on any OLED, the Galaxy S22 Plus boasts one of the best consumer displays around to use as an HDR10 reference. It can even be a reliable tool to verify the HDR tone mapping accuracy on your home-theater TV. Samsung’s phones are also the only Android handsets that utilize 100% of its peak brightness for HDR content. This is because Samsung properly tone maps the highlights towards the HDR content’s maximum peak brightness; other Android phones waste up to 25% of their peak brightness trying to tone map towards 10,000 nits. Furthermore, Samsung doesn’t place the ST.2084 reference at 100% system brightness like other Androids. Instead, Samsung places it at 75% system brightness, leaving extra room to play back HDR titles brighter than reference. This is important since the reference HDR10 home-theater viewing environment assumes an ambient brightness/surround of 5 lux/nits, which is very dim. Moreover, this is the reason why many people complain that HDR content looks too dark on other Android phones — because they have to turn their brightness up to 100% just to get it to the setting where HDR content should be viewed in a dark room.

Final Remarks

The improvements made to the displays for the Galaxy S22 lineup are exactly what I wanted to see from Samsung over the past few years. Hearing that they’ve yet again raised their peak brightness is a complete yawn. Even if it often means the panels have gotten more efficient, a couple of hundred extra nits is seldom realized in everyday use for many people.

Strictly speaking, the Galaxy S22’s new Vision Booster feature refers to the software mechanism that boosts image lightness during direct sunlight. But the reality of it seems to hint at a broader objective: content legibility. What Samsung has added to the Galaxy S22 series are changes that make their displays more pleasant to look at in more extensive scenarios — from bedtime browsing all the way up to outdoor viewing. A display that’s 20% dimmer but has appropriate tone mapping will be easier to look at in direct sunlight than a brighter display with ill-fitted contrast, which Samsung has finally come to realize.

This year, Samsung actually stagnated in terms of the development of their OLED hardware. The Galaxy S22 Ultra using the same luminous materials as last year’s is proof of this. Even though Samsung proclaimed to have squeezed out a bit more brightness this year, it’s no higher than what we’ve already measured on the previous Galaxy S21 Ultra. This is further supported by the fact that the Galaxy S22 Plus has a similar luminous power draw as the Galaxy S21 Ultra. Although I’m sure Samsung has its reasons, the cynical part of me believes Samsung knew they would be reusing its latest OLED emitters the following year, and intentionally inhibited the brightness of the first phones to use it so that they can announce an improvement for the next year.

Either way Samsung spins it, I’m not mad. The M11 luminous material set is a damn good one. At this point, I’m more anxious that Samsung’s next process of emitters —the M12 set — won’t make as good yields, such as that which occurred after the Galaxy S10 series. I’m not sure how much more Samsung Display can push its current form of OLED technology, but even if progress stumbles for a few years, I’d still be content here with what mobile OLEDs are capable of.

Perhaps it took an off-year for Samsung to assess what it can improve without pitching a higher-than-ever-before brightness metric. But if that’s what it takes, then I’d happily take another year of that.