The Sony A8F is a 2018 4k OLED TV with excellent performance for a variety of different usages. It has excellent picture quality, with perfectly deep blacks that looks impressive in a dark room. Motion handling is excellent due to the instantaneous response time, but this lack of blur can make low frame rate content appear choppy. Like the Sony A1E and other OLED TVs, it isn't perfect as the brightness changes depending on screen content and there may be risk of burn-in with static content.
The Sony A8F OLED TV is extremely well designed. The stand has a very small footprint and fits well in any decor. The TV is well built and there are no obvious gaps or loose panels. The TV has a very small frame and delivers an immersive viewing experience, especially when wall mounted.
The stand has a very small footprint and will fit on most tables. The stand adds very little height to the TV. There are two small rubber spacers (not shown) that add stability, but don't necessarily need to be on the table.
The design of the stand is significantly changed from the A1E. It takes up less space and the TV does not tilt as much.
Footprint of the 55" TV stand: 15.4" x 10.0"
The back of the TV is very clean. There are plastic panels that cover all of the bolts and connections and provide cable management.
The borders are very thin on the Sony 55A8F. When watching TV from a few feet away, they are almost not noticeable.
The Sony A8F is thin but slightly thicker than the LG C8. The electronics are more spread out over the back of the TV and it is more uniform. The screen seems to be better supported by the frame than on the C8.
The Sony A8F is cool, only getting slightly warm to the touch on three spots on the back.
Excellent build quality on the A8F. There are no obvious gaps or loose paneling. The top panel does have some flex to it, especially in the bottom corners, but this should not cause any issues.
The Sony A8F OLED TV produces excellent picture quality. It is able to produce true blacks and infinite contrast ratio, which combined with the perfect black uniformity, makes for excellent dark room performance. Can produce bright highlights and although the whole screen can't get that bright, it should be good enough to combat glare in most rooms. Color accuracy is good out of the box, and most people won't need to calibrate their set. It also has an excellent wide color gamut. It is prone to temporary image retention and could experience permanent burn-in, although we don't expect most people to experience this.
Like all OLED TVs, the Sony A8F has an infinite contrast ratio. It performs exceptionally well in a dark room.
There is no need for local dimming on OLED TVs as there is no backlight. This video is provided for reference only.
Good peak brightness with SDR content. Screen brightness varies depending on the content on screen due to the TV's ABL. The LG C8 is slightly brighter in most scenes due to the less aggressive ABL. The A8F is a little bit brighter than the A1E, but it is not a significant difference.
ABL on the A8 can be disabled by setting 'Peak Brightness' to Off, in which case the TV's brightness is constant at ~110 cd/m² regardless of content. This could be useful if watching TV in a dark room and you don't want the screen brightness to fluctuate or for PC use.
Update 02/27/2018: Retested the brightness using a PC as the source, so we can automate testing; previously we were using a Samsung K8500 Blu-ray player as the source, but we found that it was sending a brighter signal than a PC (perhaps by sending 'brighter than white' stimuli). The A8F was retested with the PC as the source, and treated this signal differently, causing its measured brightness to be ~50 cd/m² less; however, we consider this to be more accurate to most sources. The test scores have been updated.
Good peak brightness with HDR content. While far from the 1000-4000 cd/m² HDR is mastered for, it is bright enough to enjoy HDR content in most rooms. The brightness does change depending on the content due to the TVs 'Automatic Brightness Limiter' (ABL).
Great gray uniformity on the Sony A8F. There is only slight dirty screen effect in the center, this is for the most part not noticeable when watching normal content or sports.
There are vertical bands visible with our 5% test screen. These bands will be noticeable in dark scenes in a dark room.
The viewing angle is very good. Black levels remain perfect regardless of viewing angle, which is great for use as a PC monitor. There is some shift in colors when viewed off angle, but it is identical to the LG C8.
The Sony XBR55A8F has perfect black uniformity, as the OLED panel is able to turn individual pixels off in black scenes. This is especially well suited to watching movies in a dark room.
Exceptional reflection handling on the A8F. Reflections are well defined but at a much lower intensity. The TV is well suited even for a bright room.
Out of the box color accuracy is very good. Gamma almost follows our target directly, with only a small spike at the high end. Color temperature is a little warm, but most people won't notice it. Even without any calibration, the A8F is accurate for most people.
It didn't take much to calibrate the A8F. With some minor settings changes the color accuracy is excellent. Gamma follows our curve precisely, and color temperature is nearly perfect.
You can see our recommended settings here.
The A8F upscales 480p content like DVDs well. The image is not overly sharp and details stand out well.
1080p content from Blu-rays or from a game console are displayed nearly as well as native 4k.
Excellent wide color gamut on the A8F, covering nearly the entire P3 color space, nearly identical to the C8.
Great gradient handling on the Sony XBR55A8F. There is some banding visible in dark greens and reds, but overall it looks good.
The TV shows some signs of image retention even after 10 minutes of recovery.
This test is only indicative of short term image retention and not the permanent burn-in that may occur with longer exposure to static images.
Note: There is some variation between panels, even of the same model. Some panels may be more or less prone to temporary image retention.
With WRGB OLED TVs, all 4 subpixels are never on at the same time, so there are two photos.
Alternate pixel picture.
The motion handling of the Sony A8F is excellent. It has a near-instantaneous response time and is flicker-free, so there is very little motion trail and only slight persistence blur. The perfect response time causes stutter, especially with 24 fps content, but this can be helped with the optional Black Frame Insertion feature or by enabling Motion Interpolation, but it is judder-free. It does not support a variable refresh rate, and there are no plans announced by Sony to add support for this in the future.
Like all OLED TVs, the response time of the A8F is nearly instantaneous, resulting in almost no persistence blur. This is great when watching fast-paced content as there is almost no ghosting/movement trails. There is some very slight overshoot when transitioning from a black frame, but this shouldn't be noticeable.
The blur in the photo is due to persistence, not response time.
The Sony A8F is almost flicker-free, as are all OLED TVs since there is no backlight. There are small spikes approximately every 8 ms, this is not really visible as flicker though. This does result in some persistence blur, as can be seen in the response-time box photo.
Like last year's A1E, the Sony A8F has an optional BFI mode. When enabled, the TV will insert a black frame between each frame to help reduce stutter. With 120 Hz content, it drops every other frame, with 60 Hz content it cuts the frame hold time in two. If motion interpolation is enabled or with 120 Hz content, we do not recommend enabling BFI.
To enable BFI on the Sony A8F, set 'Motionflow' to 'Custom', and set 'Clearness' to 'High'.
The A8F is able to interpolate lower frame rate content up to 120Hz. This feature introduces what is know as the 'Soap Opera Effect', but helps motion appear smoother.
To interpolate 60fps content, set 'Motionflow' to 'Custom', and increase the 'Smoothness' slider. For 30fps content, set 'Cinemotion' to 'Medium' or 'High'.
Since the TV displays the full frame almost instantaneously, low frame rate content like 24fps movies stutters, especially in wide-panning shots. This can be reduced by enabling BFI or motion interpolation.
The Sony A8F displays 24p content without any judder, regardless of source.
To enable judder-free 24p playback from 60p or 60i sources like a cable box, 'Motionflow' has to be set to 'True Cinema', and 'CineMotion' as to be set to 'High'.
The A8F does not support a variable refresh rate.
The A8F supports a wide variety of input formats and resolutions. It has low 4k input lag, but not as good as the LG C8. Like all Sony TVs, only HDMI ports 2 & 3 support full bandwidth, but port 3 is also the audio return channel. If you have a receiver which supports ARC and you are planning on connecting more than 1 full bandwidth device, you may wish to consider connecting your receiver using an optical (Toslink) cable.
The Sony A8F has good input lag with a 4k signal. 1080p input lag is a bit high but good enough for all but the most competitive gamers.
These results are identical to the A1E, which uses the same processor. The LG OLED TVs have much lower input lag and are a better choice for gamers.
The Sony XBR55A8F supports all common input resolutions without any issues, including the ever more popular 1440p.
There are no issues with chroma 4:4:4 in any of the resolutions tested, including in 4k with HDR, which is great for use as a PC Monitor.
Update 06/11/2018: A note for Xbox One X and Xbox One S owners: 120 Hz from the Xbox will not work with this TV (and all 2018/2017 Sony's we've tested), because the TV requires a forced resolution for 120 Hz to be displayed.
Update 06/12/2018: It turns out 1080p @ 120 Hz is possible, when the Xbox's connection type is changed from Auto-detect (Recommended) to HDMI: (Xbox > Settings > Display & sound > Video fidelity & overscan > Display > Connection > HDMI). Unfortunately in this mode 4k, HDR, 50 Hz and 24 Hz aren't possible, so this mode is only recommended when the higher refresh rate of 120 Hz is more important to you than these other features.
Update 06/18/2018: Correction, 24 Hz and 50 Hz are in fact possible with the Xbox's connection type set to HDMI.
Wide support for most formats, including DTS passthrough which is not available on the 2018 Samsung TVs. Dolby Vision is not currently supported but it will be added later this year.
Update 06/11/2018: Dolby Vision support has been added as of firmware (PKG6.5603.0175NAA); the scores have been updated.
The Sony A8F has an above-average sound. It gets quite loud and produces a decent amount of bass along with clear dialogs. However, their bass doesn't have any thump or rumble to it, and it doesn't have a room correction system either. For a better sound, a dedicated sound system or soundbars are recommended.
The frequency response is good. Low-frequency extension (LFE) is extended down to 64Hz, which is above-average. This means that this TV can produce a good amount of punch, but won't have any thump or rumble in the bass range. Its response above the LFE is quite well-balanced, but it tapers off a bit around 8KHz. However, since this TV doesn't have a self-calibrating system, it wasn't able to remove the modes of our test room between 200Hz-300Hz. So dialog will sound clear and intelligible, but it may lack a bit of airiness. Also, it gets quite loud, but produces a bit of pumping and compression artifact under maximum load.
The distortion performance is about average. At low and moderate volumes, it produces low distortion and is within good limits. However, at max volume, like most other Sony TVs we have measured, their THD levels jump to very high amounts. However, in real-life situations, this will rarely be an issue.
The Sony A8F runs Sony's customized Android TV interface. The layout is very simple, there are multiple rows used to group similar functions together making it easy to navigate. The TV has performance issues when navigating the menus, as it froze repeatedly and animations were choppy. It is especially slow when accessing the menus from within an app. It has a great voice assistant, although it is not as good as the ThinQ AI found on 2018 LG OLEDs.
The interface is easy to use but slow. Animations are choppy and the interface stutters and freezes frequently. Performance is especially bad when accessing the menus from within an app, for example, if you are trying to change picture settings while watching Netflix.