The Sony X850F is a good 4k TV with an IPS panel. It can get bright to overcome glare and handles reflection well in a bright room but it has a very low contrast ratio so blacks appear gray when viewed in a dark room. The picture quality is decent but remains accurate when viewed at an angle which is good for those with wide seating. It also has a fast response time, which is great for watching fast-paced content. Unfortunately, Android TV isn't as streamlined or intuitive as other platforms.
The design of the Sony 2018 X850F is great. The legs, while similar to the X900F are unlike any Sony we have reviewed recently. They are wide-set and require a larger table, but there should be no issues placing a soundbar between them. There is only basic cable management at the back, similar to the X900F, but not as good as the X930E which includes routing through the back panel. The bottom edge of the TV gets a little warm to the touch. Despite being almost entirely made of plastic, the TV feels well constructed.
The stand on the X850F is unlike any other Sony TV we have reviewed. It is similar to the stand on the Samsung MU6100. It is made entirely of plastic with an aluminum finish. On our 65" model, we found them to cause the TV to wobble if it is knocked.
The footprint of the 65" TV stand: 12.0" x 43.4"
The borders of the TV look good. While slightly thicker than the 55" X900F they are still quite thin.
The Sony XBR65X850F has more of a uniform thickness than the X900F. It won't stick out from the wall much when mounted.
The bottom edge of the TV gets warm to the touch due to the edge light LEDs. There are also a few places along the back that get warm to the touch, but this should't be an issue.
The X850F feels well constructed, despite being made almost entirely of plastic. There are no obvious gaps or issues. The tabs along the back of the legs for cable management are just bent plastic. While it hasn't caused any issues for us, this could break with repeated flexing.
The picture quality of the Sony X850F is decent. It has no local dimming and a disappointing contrast ratio. It also has a good SDR brightness and an average HDR brightness, but the TV is not bright enough to fully appreciate HDR content. It has a better than average gray uniformity, but a disappointing black uniformity with a lot of clouding. The TV has a good viewing angle and is well suited to a large room. Reflections are less problematic than with the X850E. Out-of-the-box, color accuracy is average, and most of it is correctable through calibration. The color gamut is good but can't produce overly saturated greens or deep, dark colors.
Disappointing contrast ratio on the X850F. It has an IPS type panel similar to the X850D. Dark scenes will not look their best especially when playing in a dark room.
We tested the 65" model, but it is highly likely that the 85" will have a VA type panel, which we would expect to have at least a 3000:1 contrast ratio.
There is no local dimming feature on the X850F. The video is for reference only.
Better than average screen uniformity. No serious issues with dirty screen effect, which is good for watching sports or other content with large areas of uniform colors. This TV is brightest in the center and the corners are dark, which is common for TVs and isn't as distracting as uniformity issues near the center or brighter edges.
Good viewing angle. Color saturation and black levels remain good even if sitting on a wide couch or with side seating, but brightness drops sharply if sitting to the side.
We tested the 65" model which uses an IPS panel. It is highly likely that the 85" model uses a VA type panel which would have worse viewing angles.
Disappointing black uniformity. There is some obvious clouding especially around the edges. The X850F does not handle dark scenes well and would not be recommended for a dark room.
Clouding is more visible when displaying bright objects in dark scenes, since this TV does not have a local dimming feature.
The X850F has a very similar to finish to the X900F. It does not diffuse reflections as much as some other TVs.
Average color accuracy out of the box with 'Custom', 'Game', or 'Graphics' mode. Color temperature is far from our target of 6500K, so most colors have more of a yellow tint. Gamma is very close to our target of 2.2.
White balance is near perfect post calibration and color is good. Color temperature is very close to our target as is gamma. 'Custom' picture mode provided the best results.
You can see our recommended settings here.
Older 480p content is upscaled well. There are some minor artifacts but the TV handles it well.
The HDR color gamut of the X850F is good, although Rec 2020 coverage is limited. The TV has difficulty producing deeply saturated greens especially. Most scenes won't have overly saturated colors, but in very colorful scenes such as a sunset or an ocean scene the TV's limited color gamut will be noticeable.
The HDR EOTF in the 'Cinema Pro' picture mode follows the target PQ curve fairly well until it rolls off at the TV's peak brightness. The EOTFs in 'Game' and 'PC' mode are very similar to that of 'Cinema Pro', which is good.
Update 05/02/2018: The color gamut was erroneously measured at a 50% stimulus. It has been remeasured at 75% stimulus to be in line with our other TVs. It now measures slightly higher, and meets our threshold for a wide color gamut TV.
Below average color volume. The TV has difficulty displaying deep, dark colors due to the lack of local dimming and low native contrast ratio. It does not cover either color space very well.
The X850F displays gradients well. There is some banding especially in the dark colors, but not enough to bother most people.
Like most IPS and VA panels, there is no sign of temporary image retention on the X850F.
We don't expect IPS panels to have any permanent image retention. The IPS panel in our long term test has not shown any permanent burn-in.
Motion looks great on the Sony X850F. During sports and video games the TV's very fast response time reduces ghosting during motion, which is great. When watching movies and TV shows, the TV can show this motion with minimal stutter and can use optional 120 Hz soap opera effect if you want even smoother motion. And in all content, the TV's backlight has no visible flicker, which makes motion look smoother, unlike the flickering backlights of most TVs.
Great fast response time, good enough for even fast-moving content like sports. Most of the blur in the photo is due to 60 fps persistence; the ghosting trail following the logo is very short, which is excellent. This response time is very similar to the rival Samsung NU8000, but not quite as fast as the higher end Sony X900F.
The X850F has an optional BFI mode that adds flicker to make motion look more clear. Unfortunately, this flicker is limited to 120 Hz, which causes duplications in 60 fps motion, as seen in the photo; 60 Hz flicker like that of the Samsung NU8000 would be better. The X850F's flicker is activated by setting 'Motionflow' to 'Custom' and increasing the 'Clearness' slider. The X850F does not have the new 'X-Motion Clarity' feature of the X900F, so adding flicker will decrease the TV's brightness.
The X850F has a 120 Hz panel and can interpolate lower frame rate content up to 120 fps. This high frame rate greatly improves motion but can appear strange to some (the 'soap opera effect'), and sometimes adds unwanted artifacts during fast motion. Interpolation is activated by setting 'Motionflow' to 'Custom', increasing the 'Smoothness' slider, and setting 'Cinemotion' to 'High'.
The TV can show low framerate content smoothly, which is good when watching TV shows and movies. The TV's response time is long enough that completely transitioned frames aren't held on screen for a long time, which reduces the appearance of stutter.
The TV can consistently remove judder from all 24p content such as native apps, Blu-ray players, or movies from a cable box which is excellent. The TV removes judder from 24p HDMI sources automatically, but for 60p, 60i and native app sources 'Motionflow' must be set to 'True Cinema' and 'Cinemotion' to 'High' to remove judder.
Update 06/08/2018: The X850F has been retested, and can play movies from 60p or 60i sources at the correct cadence. The text above has been adjusted.
The TV does not support variable refresh rate features like FreeSync.
The Sony X850F supports all the common input signals, including HDR. It has good low input lag for 4k and 1080p signals, so there will be no issues for all but the most serious gamers. It supports chroma 4:4:4 and 1080p @ 120 Hz, which is good for use as a PC monitor.
Like all other Sony TVs we have reviewed, only HDMI ports 2 and 3 support full bandwidth, but HDMI 3 is also the audio return channel. If you have a receiver that supports ARC and more than 1 device which requires the full bandwidth of HDMI then you might have some issues connecting all of your devices. In this case, it may be best to connect your receiver using an optical (Toslink) cable.
The X850F supports all common input signals. Chroma 4:4:4 is supported in 'Game' or 'Graphics' mode. Only HDMI inputs 2 or 3 support 4k @ 60Hz @ chroma 4:4:4 or 4:2:2, and only when 'HDMI Enhanced Format' is enabled.
When in 'Graphics' mode upscaling is done by nearest neighbour when in 1080p @ 60 Hz. When sending a 120 Hz signal there is no nearest neighbour upscaling.
Update 06/12/2018: A note for Xbox One X and Xbox One S owners: 1080p @ 120 Hz from the Xbox is only supported on this TV 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.
The only combined composite/component input is located on the rear of the TV. The second composite input that was found on the side of the X850E has been removed.
The sound quality of the Sony X850F is mediocre. This TV does get loud enough for most use cases and does have a well-balanced sound in the mid and treble ranges, which is important for producing clear and natural dialogs. However, its bass is lacking a lot of punch and rumble, doesn't have a self-calibrating system to EQ the room, and produces a lot of harmonic distortion under maximum load. For a better sound reproduction, getting a dedicated soundbar is recommended.
The X850F has a mediocre frequency response. The LFE (low-frequency extension) of 120Hz is inadequate for creating the punch and rumble common to bass-heavy music and movie sound effects. The frequency response above the TV's LFE is quite well-balanced, but since it doesn't have a self-calibrating system, it wasn't able to remove our lab's room modes. This shows as a build-up of energy in the high-bass/low-mid region. On the upside, the TV does get loud enough for most use cases, and doesn't produce too much pumping and compression artifacts under heavy loads.
The harmonic distortion performance of the X850F is sub-par. At low and moderate volumes the X850F has a good THD performance. However, like most other Sony TVs we have measured, their THD jumps to very high levels under maximum load. But this will be rarely audible since most users won't need to set their TVs volume to max, and harmonic distortion is not as audible with real-life content (as opposed to with a test signal).