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Saturday, November 20, 2021

Google Pixel 6 and Pixel 6 Pro Display Review: Questionable value OLED tech - XDA Developers

Pixels are no stranger to top-end phone prices. Though all this time, it’s seemed that Google hadn’t yet released a true spiritual flagship that they were happy with—at least not until now with the Pixel 6 and Pixel 6 Pro. This year, it’s clear that Google’s new phones are the ones that the company takes pride in, but for all we know, that might just be all talk. So what better way to demonstrate the Pixel’s resurgence than to test out their effort and commitment to the display?

About this review: The Google Pixel 6 and the Google Pixel 6 Pro used for this review were personally bought from the Google Store. Google Ireland did provide my colleague Adam Conway with a Pixel 6 Pro, but the unit was not utilized for this review. Google had no involvement in the contents of this review.

Google Pixel 6

  • Great display brightness for its price
  • Good color accuracy in Natural mode
  • Inferior shadow tone control at low brightness
  • Darker colors develop a tint
  • Terrible auto-brightness system
  • Color shifts at acute angles
  • Susceptible to flaws in screen uniformity

Google Pixel 6 Pro

  • Excellent picture consistency
  • Respectable peak brightness
  • Great shadow tone control
  • Great color accuracy in Natural mode
  • Excellent grayscale precision
  • Terrible auto-brightness system

Hardware

This time around, Google changed up its release formula, opting for just one general size—big—for its two main phones. The handsets are now differentiated by their feature set, with the more premium of the two Pixel 6’s adopting the “Pro” moniker. In terms of pricing, Google surprised us with numbers that undercut its previous phones, as well as much of the competition’s, for both Pixels’ respective tiers within the smartphone market. Questionably, corners had to have been cut somewhere. With display components usually making up the largest share in a phone’s bill of materials, that’s usually where you’ll first find shortcomings.

The Pixel 6 Pro comes equipped with a sharp 6.71-inch OLED, and it has the best display hardware that Google has put on a phone till date. It uses a high-end configuration from Samsung Display, although it’s a whole step down when compared to its latest generation of OLED. This is one of those shortcomings. But considering that phones with newer display tech are generally more expensive than the Pixel 6 Pro, I’d say that its price justifies the hardware. Regardless, the panel is more than capable of delivering stunning visuals, and the 120 Hz high refresh rate makes interacting with the phone super smooth. There’s also a curve on the sides of the display that phone makers love to tack on in an attempt to make their phone look more premium, but I’m not a fan of it.

The Pixel 6 Pro's flexible OLED appears darker than the Pixel 6's rigid OLED

Pixel 6 (top); Pixel 6 Pro (bottom). The Pixel 6 Pro’s flexible OLED appears darker than the Pixel 6’s rigid OLED

Rigid OLED: a downgrade for the base model

The regular Pixel 6 uses a lower-resolution 6.40-inch Samsung panel. Although both phones are using updated OLEDs, the hardware on the Pixel 6 is actually a downgrade in some ways compared to last year’s Pixel 5. For the first time since the Pixel 2, Google is using an inferior rigid OLED display stack in their main phone lineup to cut costs. Compared to modern flexible OLEDs (like on the 6 Pro and on most flagship phones), the typical rigid display stack has lower screen contrast, fluctuant viewing angles, and appears more sunken into the display. On the upside, the Pixel 6 does get brighter, and it does appear sharper than the Pixel 5 despite having a lower pixel density (more on this later).

For the first time since the Pixel 2, Google is using an inferior rigid OLED display stack

Rigid OLEDs are an older construction that is now usually only used in budget phones. The main difference is that a rigid OLED includes a thicker glass encapsulation and substrate, while flexible OLEDs utilize a thin-film encapsulation and a bendable plastic substrate. The elastic nature of flexible OLEDs not only makes them more durable and moldable than rigid OLEDs, but it also allows for some optical advantages. Thinner encapsulation allows the physical pixels to appear closer to the cover glass, giving flexible OLEDs a more laminated look. Also, on rigid stacks, the refraction of the light transmitted through the glass layers causes unwanted rainbow viewing angles that you simply don’t see on flexible OLEDs. Lastly, not all “infinite contrast ratios” are made equal: newer flexible OLED display stacks contain darker internal materials, imposing deeper blacks than those of rigid OLEDs.

Pixel 6 (left); Pixel 6 Pro (right). The Pixel 6’s screen experiences refractions at an angle

On the Pixel 6 Pro, higher-efficiency hybrid oxide transistors support the backplane, which greatly enhances an OLED’s driving stability. This is the catalyst in enabling a true variable refresh rate, saving power as it allows pixels to hold their charge for much longer between refreshes. Since they have a low rate of discharge, oxide driving TFTs can pulse at lower currents compared to an LTPS TFT to achieve the same steady-state luminance, which further saves battery and improves calibration precision. Anecdotally, every phone that I’ve used with an LTPO panel has had near-flawless panel uniformity and very little gray tinting in low light, and I believe much of that can be also be attributed to the improved stability of the hybrid oxide backplane.

PenTile subpixel sizing

Seldom mentioned is the difference in the subpixels between PenTile OLEDs. Larger subpixels improve power efficiency and lengthen their longevity, which reduces burn-in. Higher-density screens require packing in smaller subpixels, thus there are advantages to accomodating a lower physical screen resolution. Note that this is completely different than sampling a screen at a lower render resolution, which does almost nothing for the battery outside of full-resolution gaming since the physical subpixels are still the same size.

Instead of decreasing the screen resolution, another option is to increase the panel’s fill factor, which is defined as the ratio of the subpixels’ emissive area to the total display area. For lower-resolution OLEDs, this has the added benefit of improving pixel definition, which reduces apparent color fringing around well-defined edges in the screen. Starting with the Samsung Galaxy S21, Samsung Display began to produce 1080p panels with higher fill factors, increasing the relative size of the subpixel area by about 20%. To my eyes, this had completely eliminated color fringing on these panels, and they now look closer to their non-PenTile counterparts. For those that use their phone for VR, a higher fill factor also reduces the screen door effect.

Fortunately, the Pixel 6’s 1080p screen has a high fill factor, and I observe no color fringing with it. Its screen appears sharper than 1080p PenTile screens of the past, including the higher-density panel of the Pixel 5, so those that are coming from 1440p displays need not worry too much. The OLED on the 6 Pro, however, has a lower fill ratio, so efficiency gains can be had with a better display design. Though as it stands, Apple is currently the only company that optimizes for both resolution and fill factor, with iPhone OLEDs having the largest subpixels out of any phone.

Methodology for gathering data

To obtain quantitative color data from smartphones, display test patterns are staged and measured using an X-Rite i1Display Pro metered by an X-Rite i1Pro 2 spectrophotometer in its high-resolution 3.3nm mode. The test patterns and device settings used are corrected for various display characteristics and potential software implementations that may alter desired measurements. Measurements are performed with arbitrary display adjustments disabled unless mentioned otherwise.

The primary test patterns are constant power patterns (sometimes called equal energy patterns), correlating to an average pixel level of about 42%, to measure the transfer function and grayscale precision. It’s important to measure emissive displays not only with constant average pixel level but also with constant power patterns since their output is dependent on the average display luminance. Additionally, a constant average pixel level does not inherently mean constant power; the test patterns I use are of both. A higher average pixel level closer to 50% is used to capture the midpoint performance between both the lower pixel levels and the higher pixel levels since many apps and webpages contain white backgrounds that are higher in pixel level.

The color difference metric used is ΔETP (ITU-R BT.2124), which is an overall better measure for color differences than ΔE00 that is used in earlier reviews and is still currently being used in many other sites’ display reviews. Those that are still using ΔE00 for color error reporting are encouraged to update to ΔEITP.

ΔEITP normally considers luminance error in its computation, since luminance is a necessary component to completely describe color. However, since the human visual system interprets chromaticity and luminance separately, I hold our test patterns at a constant luminance and do not include the luminance (I/intensity) error in our ΔEITP values. Furthermore, it is helpful to separate the two errors when assessing a display’s performance because, just like with our visual system, they pertain to different issues with the display. This way, we can more thoroughly analyze and understand the performance of a display.

Our color targets are based on the ITP color space, which is more perceptually uniform than the CIE 1976 UCS with much-improved hue linearity. Our targets are spaced out roughly even throughout the ITP color space at a reference 100 cd/m2 white level, with colors at 100%, 75%, 50%, and 25% saturation. Colors are measured at 73% stimulus, which corresponds to about 50% magnitude in luminance assuming a gamma power of 2.20.

Contrast, grayscale, and color accuracy are tested throughout the display’s brightness range. The brightness increments are spaced evenly between the maximum and minimum display brightness in PQ-space. Charts and graphs are also plotted in PQ-space (if applicable) for proper representation of the actual perception of brightness.

ΔETP values are roughly 3× the magnitude of ΔE00 values for the same color difference. A measured color error ΔETP of 1.0 denotes the smallest value for a just-noticeable-difference for the measured color, and the metric assumes the most critically adapted state for the observer so as not to under-predict color errors. A color error ΔETP less than 3.0 is an acceptable level of accuracy for a reference display (suggested from ITU-R BT.2124 Annex 4.2), and a ΔETP value greater than 8.0 can be noticeable at a glance, which I’ve concluded empirically.

HDR test patterns are tested against ITU-R BT.2100 using the Perceptual Quantizer (ST 2084). HDR sRGB and P3 patterns are spaced out evenly with sRGB/P3 primaries, an HDR reference white level of 203 cd/m2 (ITU-R BT.2408), and a PQ signal level of 58% for all the color patterns. All HDR patterns are tested at 20% APL with constant power test patterns.

Color Profiles

Pixel 6 Color Gamut

Pixel 6 Pro Color Gamut

Pixels offers three different color profiles to choose from, all of which change the characteristics of the colors and images on the screen.

By default, Adaptive mode is selected out of the box. Both Adaptive and Boosted modes increase color saturation just slightly, with the main difference being that Adaptive mode also uses higher contrast. Compared to the vivid profile of many other smartphones, the Adaptive mode is not as vibrant, and some people may even struggle to see the difference between Adaptive and Natural. All three profiles target a D65 white point, which might appear warm/yellow to those that aren’t accustomed to color-calibrated displays.

A small gripe I have with Adaptive and Boosted is that the color saturation increase isn’t uniform: greens are boosted the most, followed by reds, while blues have little-to-no boost (limited by the OLED’s full native gamut). There’s also nothing really “adaptive” about the profile compared to the other two, so the naming of the profile is a bit of a misnomer.

If picture fidelity is a priority, the Natural mode is the Pixel’s color-accurate profile. The profile targets the full sRGB color space (gamut, white point, and tone response) while Android’s color management system handles wide-gamut P3 content in apps that support it. Internally, Google is now also targeting Display P3 as the phone’s default composition data space, which is a small step in maturing their color management system.

For those that are not satisfied with the white balance of their Pixel, Google, unfortunately, does not provide any option to tune that aspect of the display (outside of Night Light). Google formerly had a feature called Ambient EQ on the Pixel 4 which automatically matched the white balance of the screen to the user’s ambient lighting, but the company scrapped it in its future phones for reasons unknown.

Screen Brightness

In terms of screen brightness, both the Pixel 6 and the Pixel 6 Pro perform nearly identical to each other, and they both get bright enough to use the phone under sunlight. With auto-brightness enabled, both phones get up to about 750–770 nits for fullscreen white, boosting up to 1000–1100 nits for content with lower average light levels (“APL”). Sadly the Pixel 6 and 6 Pro can only maintain their high brightness mode for five minutes at a time out of every thirty minutes, so using the phone extensively outside may not be ideal. After five minutes, the phone display will ramp down to about 470 nits, which is both phones’ maximum manual brightness when auto-brightness is disabled.

For the cost of the regular Pixel 6, these figures showcase excellent value

For the Pixel 6 Pro, these peak brightness values are standard and to be expected considering its price. But for the cost of the regular Pixel 6, these figures showcase excellent value, and phones that do get brighter generally cost a bit more than even the 6 Pro.

Apart from peak brightness, display tone mapping also plays a big role in improving a screen’s legibility under sunlight. This will be covered more later on, but in short, the Pixel 6 and Pixel 6 Pro does boost shadow tones to help out with outdoor viewing.

When set to their dimmest brightness setting, the Pixel 6 and Pixel 6 Pro can get down to about 1.8–1.9 nits, which is typical of most, but not all OLED phones (namely OnePlus). At this brightness, the default Adaptive profile on both phones crushes near-black colors due to the profile’s steeper contrast curves. Natural mode exhibits lighter shadows, and on the Pixel 6 Pro the profile retains distinct shadow details with very little black clipping in low light. The Pixel 6, on the other hand, struggles a bit more with near-black colors, especially in its 90 Hz state.

Auto-brightness

The auto-brightness system on the Pixels has been the worst that I’ve used in any recent phone. One common argument is that it learns your brightness preference over time, but the underlying framework is fundamentally flawed in a way that fancy machine learning can’t fix. The result of the system is jittery transitions and a lack of resolution in the low end.

Pixel brightness mapping. Jittery transitions for low brightness values

Pixel brightness mapping (estimated). Jittery transitions for low brightness values

Before the Pixel 6, Google only reserved 255 distinct brightness values to control the display brightness. Even if all brightness values were to be efficiently spaced out, the resolution simply wasn’t enough to create perfectly smooth transitions. Now with the Pixel 6, Google increased the internal number of brightness values up to 2043 between 2 nits and 500 nits. That seems like it should be sufficient, but there are two important details: the mapping of those brightness values, and how the Pixel transitions through those brightness values.

Although the Pixel 6 has 2043 brightness values, those values are mapped linearly to its display brightness. This means that the spacing of brightness between those values is not perceptually uniform, since the human perception of brightness scales somewhat logarithmically, rather than linearly, in response to screen luminance nits. In Android 9 Pie, Google altered the Pixel’s brightness slider so that it would scale logarithmically instead of linearly for the reason that I just mentioned. However, this only changed how the position on the brightness slider mapped to the system brightness value, which is still internally linear.

Even with the higher brightness resolution of the Pixel 6, jitters can be seen between the brightness values below about 30% system brightness. For this inherent reason, the Pixel’s transition in display luminance can appear jumpy when the auto-brightness moves around in low light. The jitteriness is exacerbated by the speed and the behavior of the Pixel’s auto-brightness transitions, which steps linearly through display luminance at a constant pace that reaches max brightness from minimum brightness in one second—or about 500 nits per second. This makes any auto-brightness transition virtually instantaneous for small-to-medium adjustments.

Power consumption

Display Power of Pixel 6, Pixel 6 Pro, S21 Ultra.

Display Power of Pixel 6, Pixel 6 Pro, S21 Ultra.

Quickly touching on display power: When focusing on fullscreen display nits per watt, the Pixel 6 Pro consumes substantially more power than the Pixel 6 at high brightness. This is somewhat expected since the Pro has a slightly larger display and a higher resolution (read: smaller emissive pixel area), though I did not expect the difference to be this dramatic. Adding in the Samsung Galaxy S21 Ultra as another data point, it consumes less power than both Pixels despite having a larger screen, which showcases the impeccable efficiency gains of Samsung’s next-gen OLED emitters. The discrepancy in variable refresh rate was not tested.

Contrast & Tone Mapping

A general rule of thumb in calibrating a display is to target a gamma power of 2.4 for dark rooms, or 2.2 for everywhere else. Smartphones are used in all sorts of viewing conditions, so they typically fall in the latter category. Hence, most phones target a gamma power of 2.2 for their standard calibrated display modes. This is what the Pixel had always done, but it’s a little different this year on the Pixel 6 and Pixel 6 Pro.

Pixel 6 Tone Response (Natural, 1.8 nits)

Pixel 6 Tone Response (Natural, 20 nits)

Pixel 6 Tone Response (Natural, 100 nits)

Pixel 6 Tone Response (Natural, 400 nits)

Pixel 6 Tone Response (Natural, 750 nits)

Pixel 6 Tone Response (Adaptive, 1.8 nits)

Pixel 6 Tone Response (Adaptive, 20 nits)

Pixel 6 Tone Response (Adaptive, 100 nits)

Pixel 6 Tone Response (Adaptive, 400 nits)

Pixel 6 Tone Response (Adaptive, 750 nits)

Pixel 6 Pro Tone Response (Natural, 2 nits)

Pixel 6 Pro Tone Response (Natural, 20 nits)

Pixel 6 Pro Tone Response (Natural, 100 nits)

Pixel 6 Pro Tone Response (Natural, 400 nits)

Pixel 6 Pro Tone Response (Natural, 800 nits)

Pixel 6 Pro Tone Response (Adaptive, 2 nits)

Pixel 6 Pro Tone Response (Adaptive, 20 nits)

Pixel 6 Pro Tone Response (Adaptive, 100 nits)

Pixel 6 Pro Tone Response (Adaptive, 400 nits)

Pixel 6 Pro Tone Response (Adaptive, 800 nits)

New tone responses: Gamma 2.2 vs Piecewise sRGB

In the default Adaptive mode, the Pixel 6 and Pixel 6 Pro have increased contrast compared to the other profiles. The tone response is approximately a 2.4 gamma power on the Pixel 6, while on the Pixel 6 Pro it’s more like gamma 2.3. At lower brightness levels, the Adaptive mode has too much contrast in my opinion, and a number of near-black colors can appear completely clipped, especially on the cheaper phone.

For the Natural and Boosted profiles, the Pixel 6 and the Pixel 6 Pro now conform to the piecewise sRGB tone response curve rather than gamma 2.2. The curve differs in that it has a linear mapping near black which makes dark tones appear lighter compared to gamma 2.2.  Due to the increased complexity of the function, most people just calibrate to gamma 2.2 for simplicity, and it’s what monitor calibrators and artists have been doing for many years. The actual use of the precise sRGB curve is a controversial topic for this reason; even though it’s the “official” standard, it creates disparity among the vast majority who have already been working with gamma 2.2, which many argue to be the “correct” industry standard.

What makes this interesting is that I’m not sure Google even intended for this behavior. Samsung also ships phones with the sRGB tone curve, though only on their Exynos variants—the Snapdragon models still use gamma 2.2. The Exynos display pipeline inside the Pixels’ Tensor SoC is likely responsible for decoding RGB triplets with the sRGB transfer function.

In regards to accuracy, both phones do a good job tracking the sRGB tone curve in their Natural and Boosted mode. But at lower brightness, the Pixel 6 fails to keep up with the performance of the Pixel 6 Pro as the cheaper panel struggles to lift darker tones in its 90 Hz clock rate. In general usage, the sRGB tone curve looks close enough to the standard 2.2 gamma curve to where most people won’t notice a difference for most imagery. However, a lift in shadows is definitely observable in the darker regions of content and in dark-themed interfaces. Some may prefer this look over gamma 2.2, while others may think it looks washed out. Personally, I prefer this tonal appearance on smartphones for the enhanced legibility in low light and in bright conditions.

When high brightness mode triggers under a sunny day, the displays will bump up the shadows, with the Pro phone being capable of being tuned a bit brighter. This helps improve the visibility of image details in brighter conditions without compromising the image quality.

Shadow tone control

At their dimmest setting, the Pixel 6 Pro paints a much more tonally balanced screen. In its Natural mode, the Pixel 6 Pro is one of the best-performing low brightness OLEDs on any phone. I claimed the same thing for last year’s Pixel 5, which had impeccable shadow tone control. Compared to it, the Pixel 6 Pro performs similarly, though this year’s display is just slightly worse near black. While the Pixel 5 was able to render its first bit step out of black (1/255) at all brightness levels, the Pixel 6 Pro can only do so at high brightness. It does globally render the very next step, however, and in my book, that’s still fantastic. The Pixel 5’s shadows were also a bit lighter overall in low light, but in my opinion it made things look a little too flat, and I now prefer the look of the 6 Pro.

The Pixel 6 Pro is one of the best-performing low brightness OLEDs on any phone

Within the same conditions, the non-Pro Pixel does not compete. The cheaper display renders steep shadows that clip a little more near black, and in Adaptive mode, the Pixel 6 becomes a mottled mess at minimum brightness. For this reason, I cannot recommend the profile on Pixel 6.

White Balance & Grayscale Precision

Pixel 6 Grayscale (2 nits)

Pixel 6 Grayscale (20 nits)

Pixel 6 Grayscale (100 nits)

Pixel 6 Grayscale (400 nits)

Pixel 6 Grayscale (750 nits)

Pixel 6 Pro Grayscale (2 nits)

Pixel 6 Pro Grayscale (20 nits)

Pixel 6 Pro Grayscale (100 nits)

Pixel 6 Pro Grayscale (400 nits)

Pixel 6 Pro Grayscale (800 nits)

Nominally, both displays strike very similar white points that measure decently accurate to D65/6504 K. Both my units erred slightly on the magenta side, though I have no qualms with this as I’ll explain later.

Under the surface, the two phones actually perform vastly different when it comes to color precision. The Pixel 6 Pro maintains the color of its white throughout its grayscale and throughout its brightness range, with the exception of high-brightness mode where the tint in darker colors will likely be masked by sunlight. The Pixel 6, on the other hand, progressively tints towards magenta the lower the color tone intensity. A mild flicker was also visible when the Smooth Display auto-switched between 90 Hz and 60 Hz, but on my sample, the effect isn’t too noticeable. Lastly, on my unit, the non-uniform grayscale distribution is painfully obvious at lower brightness.

“Metameric failure”

Two colors from different displays that measure the same exact chromaticity don’t necessarily appear identical in color. The fact of the matter is that current methods of color measurement don’t provide a definitive assessment for color matching. As it turns out, the difference in spectral distributions between OLEDs and LCDs creates a disagreement in the appearance of their white points. More precisely, the color of white on OLEDs will typically appear yellowish-green compared to an LCD display that measures identically. This is known as metameric failure, and it’s been widely acknowledged to occur with wide-gamut displays such as OLEDs. The standard illuminants (e.g. D65) have been defined with spectral distributions that match closer to that of an LCD, so the technology is now used as a reference. For this reason, an offset towards magenta is needed for the white point of OLEDs to perceptually match the two display technologies.

Now, I’m not saying that metameric failure is the reason why the Pixel 6 (Pro) displays measure towards magenta, but there’s a point to be made about looking at just colorimetric measurements alone. For reference, this is how the white point of the Pixel 6 Pro measures when it’s perceptually color-matched to my calibrated LCD monitor. The difference is massive. There have been many attempts in methodologically transferring over the perceptual appearance, but none have been comprehensive enough to cover every emerging display type—matching by eye is quite literally the best way to do this at the moment. Nevertheless, accurate measurements to any standard allow for predictability if adjustments are to be made, which is a critical attribute for any electrical component.

Color Accuracy

The formula for good color accuracy is quite simple: accurate tone mapping plus an accurate white point. The previous sections of this review can almost entirely deduce the rest of the displays’ color mixing performance. Pretty charts and quantitative verification are always nice though, so here they are.

Pixel 6 sRGB Color Accuracy (Natural, 2 nits)

Pixel 6 sRGB Color Accuracy (Natural, 20 nits)

Pixel 6 sRGB Color Accuracy (Natural, 100 nits)

Pixel 6 sRGB Color Accuracy (Natural, 400 nits)

Pixel 6 sRGB Color Accuracy (Natural, 750 nits)

Pixel 6 P3 Color Accuracy (Natural, 2 nits)

Pixel 6 P3 Color Accuracy (Natural, 20 nits)

Pixel 6 P3 Color Accuracy (Natural, 100 nits)

Pixel 6 P3 Color Accuracy (Natural, 400 nits)

Pixel 6 P3 Color Accuracy (Natural, 750 nits)

 

Pixel 6 Pro sRGB Color Accuracy (Natural, 2 nits)

Pixel 6 Pro sRGB Color Accuracy (Natural, 20 nits)

Pixel 6 Pro sRGB Color Accuracy (Natural, 100 nits)

Pixel 6 Pro sRGB Color Accuracy (Natural, 400 nits)

Pixel 6 Pro sRGB Color Accuracy (Natural, 800 nits)

Pixel 6 Pro P3 Color Accuracy (Natural, 2 nits)

Pixel 6 Pro P3 Color Accuracy (Natural, 20 nits)

Pixel 6 Pro P3 Color Accuracy (Natural, 100 nits)

Pixel 6 Pro P3 Color Accuracy (Natural, 400 nits)

Pixel 6 Pro P3 Color Accuracy (Natural, 800 nits)

 

Natural mode on both phones demonstrates fine-tuned color accuracy, with average color errors ΔETP less than 3.0, and maximum color errors ΔETP less than 10.0. These values are sufficient enough for a reference display, though it’s important to note that these color measurements were taken at 75% tone intensity; the poor color precision on the cheaper Pixel 6 display means that it’s expected to perform worse at lower tone intensities, while the Pro display remains accurate independent of tone intensity. Besides that, there is some mild skewing with more-complex color mixtures, such as with purple and orange, due to the different tone response curve that Google is using. No doubt that if it stuck with gamma 2.2, the Pixel 6 and Pixel 6 Pro would measure even more accurately, though the difference would mostly be academic.

In high-brightness mode, the displays will slightly crank up the color saturation to overcome the saturation loss from viewing glare. This together with the contrast lightness boost should help the display look more accurate under sunlight.

HDR10 Playback

Although HDR content still isn’t all too common, many newer titles on streaming platforms have now been releasing masters in Dolby Vision and HDR10. To help with adoption, a number of smartphones provide the capability to record in one of the existing HDR formats. Out of the existing phones, Apple’s iPhones have been the ones to propel the demand for platform adoption of the HDR formats with their Dolby Vision-/HLG-enabled recording. In my assessment, however, I only cover the HDR10 format, which is currently the most ubiquitous format for professional content creators.

Excellent tone control, precision, and color accuracy carries over to HDR10 on the Pixel 6 Pro. The ST.2084 standard HDR tone response curve is faithfully reproduced along with incredibly consistent color temperature all throughout its grayscale. This assures that the white balance and contrast of every scene can replicate the creator’s visual intent, at least up to 650 nits. Most HDR content that is currently being delivered through streaming platforms is mastered or optimized for a maximum headroom of 1,000 nits for highlights. The Pixel 6 Pro is able to get up to 800 nits fullscreen brightness, but a lack of metadata-aware tone mapping brings the usable in-content peak down to about 650 nits. While the 350-nit deficit may seem substantial, not many scenes in practice are graded much brighter.

As for the regular Pixel 6, it’s still capable of delivering brilliant visuals, just without as much polish. Scenes can vary in white balance on the cheaper OLED due to lower-brightness tinting, and image contrast is generally a little steeper. Shadow definition is also not as polished as on the Pro display.

The gotcha is that all the above assume a viewing environment of 5 lux, which is the status quo for HDR10. This is considerably dim for casual watching, and most people in actuality will watch things in a brighter setting. Furthermore, standard HDR10 replication is calibrated for maximum system brightness, so if you intend to watch a show in HDR10 inside a brighter room, the experience won’t be optimal since the display brightness can’t be set any higher. HDR10 is also implemented this way in most TVs, not just on the Pixel 6 or on Android, but newer TVs also offer adaptive adjustments to the HDR tone mapping to compensate for brighter environments. The Pixel 6’s 650-nit effective peak along with its lack of adaptive tone mapping means that it can’t deliver the same strong HDR performance outside of a dimly lit room.

Final Remarks

Two different phones, therefore two different conclusions.

For its highest-end handset, Google delivers some of the best color reproduction and image consistency that you can find on any consumer display. With the Pixel 6 Pro, you can be certain that you’re seeing all the picture details at any brightness level, be it dim or bright. On the contrary, the color tuning may be the reason why some people won’t like it. Even in its most vibrant color mode, the display still behaves on the more color-accurate side, so those that prefer a high-saturation appearance may be left wanting more. Additionally, the Pixel 6 Pro doesn’t carry the brightest or the most efficient OLED tech, but its current capabilities are perfectly adequate and well worth its price tag. It’s understandable that people would want the absolute best panel available from the best phone that Google offers, but the Pixel 6 Pro is just not priced in that manner.

With the Pixel 6 Pro, you can be certain that you're seeing all the picture details at any brightness level

Speaking of price, the cheaper phone, unsurprisingly, uses a cheaper display. And by cheaper, I do mean cheap. From crude viewing angles to irregular screen uniformity and grayscale tinting, the OLED on the Pixel 6 is very much a budget-level phone experience—one that you would expect from their Pixel A-series. For what’s supposed to be one of Google’s two strongest offerings, the choice of OLED on the Pixel 6 makes it feel like an unpolished product, and in my opinion, it completely cheapens the brand. We don’t find this level of compromise on the display of any other flagship “non-Pro” variants from the competition.

Despite the rest of the handset feeling quite premium, the screen is just too important of a component to skimp out on. Many people have criticized Apple for adopting OLED so late inside their base models, but in its defense, using the Pixel 6 made it understandable why Apple had decided not to just include any cheap rigid OLED in their phones. They simply lack the refinement that is expected from a premium handset. For its price point, I don’t think it could be helped; by undercutting the competition by $100–$200 USD, the Pixel 6 inevitably had to make some sort of glaring sacrifice. So, rather than just being a well-priced premium phone, what this showed me was that the Pixel 6 is truly more of a mid-range device, in a tier that is more similar to Apple’s “R”-series or Samsung’s “FE” variant.

For what's supposed to be one of Google's two strongest offerings, the choice of OLED on the Pixel 6 makes it feel like an unpolished product

Within the Pixel software, some accommodations could have been made to enhance the user experience. For starters, improvements to the auto-brightness are sorely needed, as its transitions turn out to be jarring more often than not. I would also appreciate the return of AmbientEQ, which was the automatic white balance feature in the Pixel 4. Manual adjustments to the screen white balance would also be helpful, which could be used to tune the screen color temperature to your taste, or even to compensate for the metameric failure.

Google Pixel 6 Forums | Google Pixel 6 Pro Forums

Overall, I’m torn on whether I like the direction that Google has taken for the displays of its two main phones. Of course, everyone would want them both to be a bit better—a slightly brighter display for the 6 Pro and a more refined OLED for the regular 6—but Google’s pricing has made it difficult to ask for more. At least for the Pro phone, I genuinely believe that you’re getting your money’s worth. But for the upper mid-ranged Pixel 6, I feel that it’s priced in a guttered region where it’s not priced high enough to afford a display that sets it apart from those on budget phones. If Google priced the Pixel 6 about $100 higher, but with a polished flexible OLED to boot, I believe that Google’s base model could be much more successful.

    Google Pixel 6
    Google's standard Pixel model comes with a 90 Hz 1080p rigid OLED
    Google Pixel 6 Pro
    Google's best phone, equipped with a high-resolution 120 Hz LTPO flexible OLED
Specification Google Pixel 6 Google Pixel 6 Pro
Technology

Rigid OLED

PenTile Diamond Pixel

s6e3fc3

8-bit

Flexible OLED

PenTile Diamond Pixel

s6e3hc3

8-bit

Manufacturer Samsung Display Co. Samsung Display Co.
Size

5.8 inches by 2.6 inches

6.40-inch diagonal

15.4 square inches

6.1 inches by 2.8 inches

6.71-inch diagonal

17.0 square inches

Resolution

2400×1080

20:9 pixel aspect ratio

3120×1440

19.5:9 pixel aspect ratio

Pixel Density

291 red subpixels per inch

411 green subpixels per inch

291 blue subpixels per inch

362 red subpixels per inch

512 green subpixels per inch

362 blue subpixels per inch

Brightness

Minimum:

1.8 nits

Peak 100% APL:

746 nits

Peak 50% APL:

909 nits

Peak HDR 20% APL:

770 nits

Minimum:

1.9 nits

Peak 100% APL:

766 nits

Peak 50% APL:

901 nits

Peak HDR 20% APL:

801 nits

White Balance Standard is 6504 K

6400 K

ΔETP = 4.4

6510 K

ΔETP = 2.6

Tone Response Standard is a straight gamma of 2.20

Natural:

Piecewise sRGB

Gamma 2.04–2.34


Adaptive:

Gamma 2.34–2.56

Natural:

Piecewise sRGB

Gamma 1.94–2.00


Adaptive:

Gamma 2.22–2.32

Color Difference ΔETP values above 10 are apparent ΔETP values below 3.0 appear accurate ΔETP values below 1.0 are indistinguishable from perfect

Natural:

sRGB:

Average ΔETP = 3.0

Max ΔETP = 9.2

P3:

Average ΔETP = 3.0

Max ΔETP = 9.2

Natural:

sRGB:

Average ΔETP = 2.7

Max ΔETP = 7.8

P3:

Average ΔETP = 2.9

Max ΔETP = 8.4

Black Clipping Threshold Signal levels to be clipped black

Natural:

<2/255 @ 100 nits

<1/255 @ 20 nits

<4/255 @ min brightness


Adaptive:

<3/255 @ 100 nits

<1/255 @ 20 nits

<13/255 @ min brightness

Natural:

<1/255 @ 100 nits

<2/255 @ 20 nits

<2/255 @ min brightness


Adaptive:

<1/255 @ 100 nits

<5/255 @ 20 nits

<2/255 @ min brightness

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