LG SK9000 TV Review

Tested using Methodology v1.5
Updated Apr 20, 2018 at 10:19 am
LG SK9000 Picture
Mixed Usage
Value for price beaten by
: no price info
TV Shows
Video Games
HDR Movies
HDR Gaming
PC Monitor
This TV was replaced by the LG SM9000
Type LED
Resolution 4k

The Super UHD LG SK 9000 is a 4k TV with very good performance for a range of usages. The picture quality is good in a bright room, and the TV can get bright to overcome glare. It also has great reflection handling, and the image remains accurate when viewed at an angle. Unfortunately, the dark-room performance is sub-par as the native contrast ratio is low and blacks appear gray, despite the full-array local dimming.

Our Verdict

7.4 Mixed Usage

Very good TV for a wide range of usages. The TV is best suited for bright rooms with wide seating, as it can get bright to combat glare and has great reflection handling. Image remains accurate when viewed at an angle which is great. Picture quality in a dark room is sub-par as the full-array local dimming isn't enough to make up for the low native contrast ratio. Input lag is very low and motion handling is good, so the TV feels responsive for gaming or PC use.

  • Image remains accurate when viewed at an angle
  • Feels very responsive for gaming
  • Can produce bright highlights
  • Blacks appear gray in a dark room
6.9 Movies

Decent for watching movies in a dark room. Full-array local dimming helps to alleviate the poor native contrast ratio but blacks still appear gray or details are crushed in dark scenes. The TV can display 24p movies from most sources without judder which is great.

8.1 TV Shows

Great for watching TV shows in a bright room. The LG SK 9000 can get bright in SDR to combat glare, and reflection handling is great. Image also remains accurate when viewed from an angle, which is good for those with wide seating. The smart platform works well for casual browsing or finding content on Netflix and YouTube.

7.8 Sports

Great for watching sports in a bright room. Image remains accurate when viewed at an angle which is great for gatherings for an important game. The response time is fast, which is great for displaying fast motion without much of a trail. The screen can get bright to overcome glare, and anti-reflective coating works great.

7.6 Video Games

Great for gamers. Input lag is very low, so games feel responsive. The response time is excellent, resulting in only a short blur trail behind fast-paced content. The LG SK9000 can also flicker the image to clear up fast motion, and the picture quality is good in a room with some light.

6.8 HDR Movies

Decent choice for watching HDR movies in a dark room. Contrast ratio is low so blacks appear gray, even with full-array local dimming. The TV can produce bright and saturated highlights. It supports both HDR10 and Dolby Vision.

7.0 HDR Gaming

Great for HDR gaming. Picture quality is good, but low contrast ratio results in dark scenes that appear gray or washed out in a dark room. Input lag is low and response time is excellent so the TV feels very responsive even in fast action sequences. The TV can produce bright and saturated highlights in HDR.

8.0 PC Monitor

Great for use as a monitor. The colors remain accurate at an angle, which is great for viewing the sides of the screen from up close. Supports chroma 4:4:4 for clear text across all backgrounds. Input lag and fast response time are low, so the TV feels responsive and movement is clear.

  • 7.4 Mixed Usage
  • 6.9 Movies
  • 8.1 TV Shows
  • 7.8 Sports
  • 7.6 Video Games
  • 6.8 HDR Movies
  • 7.0 HDR Gaming
  • 8.0 PC Monitor
  1. Update 5/21/2020: Converted to Test Bench 1.5.
  2. Update 2/21/2020: Converted to Test Bench 1.4.
  3. Update 2/28/2019: Converted to Test Bench 1.3.

Test Results

Curved No

The design of the LG SK9000 is very similar to last year's SJ8500. It has the same familiar curved stand, although it is a bit thinner this year and there is a bit more flex to the stand. The color of the frame is more uniform, with a black back instead of the white back of last year's model. There are some practical limitations as there is only very basic cable management and the stand does not allow you to place a soundbar directly in front of the TV.


The stand is curved and looks very similar to last year's SJ9500. It has a slightly darker metal finish and is slightly narrower. The stand does wobble a bit if the floor shakes.

Footprint of the 55" TV Stand: 9.8" x 32.5"

Wall Mount VESA 300x300

The rear of the LG 55SK9000 is very similar to the SJ8500, except all black. There is only basic cable management as seen here.

Borders 0.43" (1.1 cm)

The borders of the TV are thin, and look great. Similar to the SJ9500, the bezel does not surround the LCD panel. The panel is attached on top of the frame and could be damaged if knocked on the side. Care should be taken when moving the TV, as it could be damaged if knocked, similar to what happened to our SJ8500.

Max Thickness 1.89" (4.8 cm)

The TV has an average thickness but appears thin when viewed from the side due to the gentle angles of the back. It does not stick out when wall mounted.

Build Quality

Good build quality. We noticed a small gap between the main panel and exterior bezel, but this should not be an issue. Like the SJ8500, the LG 55SK9000 is almost entirely plastic, but there isn't too much flex.

Picture Quality
Picture Quality
Native Contrast
1306 : 1
Contrast with local dimming
1311 : 1

The native contrast ratio on the SK9000PUA is decent, as is typical of IPS panels. When in a dark room, blacks will look more gray than black. This is less noticeable when in a brightly lit room.

The local dimming feature is ineffective at increasing the contrast ratio.

Picture Quality
Local Dimming
Local Dimming

The local dimming feature on the SK9000 is not responsive enough. It reacts too slowly to moving highlights, and the dimming zones turn on and off too late. It is very similar to the Vizio M Series 2017. We do not recommend using the 'High' setting. 'Medium' or 'Low' work best depending on personal preference.

Picture Quality
SDR Peak Brightness
SDR Real Scene Peak Brightness
458 cd/m²
SDR Peak 2% Window
152 cd/m²
SDR Peak 10% Window
357 cd/m²
SDR Peak 25% Window
410 cd/m²
SDR Peak 50% Window
446 cd/m²
SDR Peak 100% Window
464 cd/m²
SDR Sustained 2% Window
151 cd/m²
SDR Sustained 10% Window
354 cd/m²
SDR Sustained 25% Window
408 cd/m²
SDR Sustained 50% Window
445 cd/m²
SDR Sustained 100% Window
464 cd/m²

Very good SDR peak brightness, bright enough for most rooms. Highlights appear dim, this is due to the poor local dimming feature. If you find highlights too dim, set the 'Local Dimming' setting to Low or Off.

This test was done with the 'Contrast' set to '90', which is our recommended value to get the brightest TV possible without causing white crush.

Picture Quality
HDR Peak Brightness
HDR Real Scene Peak Brightness
520 cd/m²
HDR Peak 2% Window
427 cd/m²
HDR Peak 10% Window
1180 cd/m²
HDR Peak 25% Window
764 cd/m²
HDR Peak 50% Window
586 cd/m²
HDR Peak 100% Window
547 cd/m²
HDR Sustained 2% Window
181 cd/m²
HDR Sustained 10% Window
362 cd/m²
HDR Sustained 25% Window
461 cd/m²
HDR Sustained 50% Window
525 cd/m²
HDR Sustained 100% Window
545 cd/m²

Decent peak HDR brightness. Very small highlights are only noticeable in the sense that they are dimmer than the rest, again a symptom of the poor local dimming. Real scenes are bright enough for most rooms, although still far from the target 1000 cd/m² to fully appreciate HDR content.

Picture Quality
Gray Uniformity
50% Std. Dev.
4.790 %
50% DSE
0.239 %
5% Std. Dev.
0.629 %
5% DSE
0.096 %

Decent overall gray uniformity on the LG SK 9000. The sides of the screen are darker than the rest, but this is not as noticeable as when it is darker in the center. There is noticeable dirty screen effect in the center; this will be especially noticeable when watching sports.

Picture Quality
Viewing Angle
Color Washout
29 °
Color Shift
65 °
Brightness Loss
33 °
Black Level Raise
70 °
Gamma Shift
43 °

Mediocre viewing angle on the SK9000, far better than most TVs with VA panels, but far worse than TVs with OLED panels. Colors and brightness shift when viewing off angle, making this TV an okay, but less than ideal choice for a room where people will frequently be watching from the side of the TV.

Picture Quality
Black Uniformity
Native Std. Dev.
2.343 %
Std. Dev. w/ L.D.
2.598 %

Poor black uniformity on the SK9000. When local dimming is off, there is noticeable backlight bleed across most of the screen.

With local dimming set to 'High', there is visible blooming around the image. The full array local dimming on the SK9000 is turning the zones off, but the results are much worse than other FALD TVs like the Sony X900F.

Picture Quality
Screen Finish
Total Reflections
3.4 %
Indirect Reflections
0.5 %
Calculated Direct Reflections
2.9 %

Decent reflection handling on the SK 9000, identical to the SJ8500. The semi-gloss finish diffuses reflections a bit, reducing their intensity. These results should be fine for most rooms.

Picture Quality
Pre Calibration
White Balance dE
Color dE
Color Temperature
6139 K
Picture Mode
Expert (Dark Room)
Color Temp Setting
Warm 2
Gamma Setting

The most accurate results out of the box were obtained with the 'Expert (Dark Room)' picture mode. Color and White Balance dE were good, but the color temperature was cold, giving everything a slightly blue tint. The color and white balance delta is low enough that most people won't notice.

Picture Quality
Post Calibration
White Balance dE
Color dE
Color Temperature
6508 K
White Balance Calibration
20 point
Color Calibration
Auto-Calibration Function

Excellent white balance after calibration. Color dE was still a bit high, as the Color Management System in the SK9000 was not very effective at correcting the blue errors. Gamma is very close to our target, shifting a little off target at the low and high end of our inputs.

You can see our recommended settings here.

Picture Quality
480p Input

There were no obvious issues upscaling older 480p content like DVDs on the LG SK9000.

Picture Quality
720p Input

720p content is scaled well on the SK 9000 with no obvious over softening or artifacts.

Picture Quality
1080p Input

1080p content, like Blu-rays look good.

Picture Quality
4k Input

Native 4k content is clear and sharp.

Picture Quality
8k Input
Picture Quality
Picture Quality
Color Gamut
Wide Color Gamut
DCI P3 xy
88.98 %
DCI P3 uv
94.51 %
Rec 2020 xy
65.97 %
Rec 2020 uv
73.14 %

Good coverage of the P3 color space, the TV is able to display a wide color gamut.

The HDR EOTF in the 'Technicolor Expert' picture mode is too bright for most of our PQ curve, and rolls of gradually at the peak brightness of the TV. The 'PC' and 'Game' EOTF curves are very similar to that of 'Technicolor Expert', which is good.

When displaying HDR content in 'PC Mode', the SK9000 does not properly detect the wide color gamut so colors appear washed. This is the same as the C8.

Picture Quality
Color Volume
Normalized DCI P3 Coverage ITP
76.7 %
10,000 cd/m² DCI P3 Coverage ITP
34.5 %
Normalized Rec 2020 Coverage ITP
62.1 %
10,000 cd/m² Rec 2020 Coverage ITP
27.3 %

Decent color volume, but the LG 55SK9000 is unable to produce deep, dark blacks due to its poor contrast ratio and ineffective local dimming. It is also inconsistent in producing bright saturated colors. Color volume is worse than last year's SJ8500.

Picture Quality
Color Depth
10 Bit
Red (Std. Dev.)
0.101 dE
Green (Std. Dev.)
0.120 dE
Blue (Std. Dev.)
0.093 dE
Gray (Std. Dev.)
0.064 dE

There were some issues with the SK9000's gradient handling that are not reflected in our testing score. Large areas of near-uniform color showed large areas of banding, worse than the C8. This can be reduced by enabling the TV's 'MPEG Noise Reduction' feature, which enables the gradient smoothing feature of the SK 9000. This helps reduce banding but also causes a loss of detail.

Picture Quality
Temporary Image Retention
IR after 0 min recovery
0.06 %
IR after 2 min recovery
0.00 %
IR after 4 min recovery
0.00 %
IR after 6 min recovery
0.00 %
IR after 8 min recovery
0.00 %
IR after 10 min recovery
0.00 %

The TV does show some signs of image retention. Only a faint outline of the logo is visible, and it is completely gone before 2 minutes recovery. It is an improvement over the SJ8500, and there is not enough persistence for it to be an issue for most people.

Picture Quality
Permanent Burn-In Risk
Permanent Burn-In Risk

While IPS panels can have some temporary image retention, there doesn't appear to be any risk of permanent burn-in as seen in our long-term test.

Response Time
80% Response Time
5.1 ms
100% Response Time
14.4 ms

Excellent response time on the LG 55SK9000PUA, great for watching sports or fast paced movies. Most of the blur visible in the photo is caused by 60 fps persistence when there is no flicker, but there is a small motion blur trail behind the logo. There is some overshoot on the 100% transitions but it is minor and should not cause any ghosting. Only a short trail can be seen following fast-moving objects.

PWM Dimming Frequency
120 Hz

The SK9000PUA uses PWM to dim the backlight, which helps to clear up motion slightly, but results in some duplications following fast-moving objects, as can be seen in the motion blur box photo. This causes the backlight to flicker, starting at any backlight setting other than '100'. It uses a different type of PWM dimming than the SJ8500, so it is a bit less noticeable. People sensistive to flicker should consider a nearly flicker-free alternative, like the Sony X900F.

Black Frame Insertion (BFI)
Optional BFI
Min Flicker for 60 fps
60 Hz
60 Hz for 60 fps
120 Hz for 120 fps
Min Flicker for 60 fps in Game Mode
60 Hz

When 'Motion Pro' is enabled, the backlight flickers to match the refresh rate of the content on the screen to reduce persistence blur. With 120 Hz content the natural refresh rate of the backlight is better, so Motion Pro' must be set to Off.

Motion Interpolation
Motion Interpolation (30 fps)
Motion Interpolation (60 fps)

The SK 9000 has a native 120hz panel and can interpolate lower frame rate content up to 120 fps. Motion interpolation can look very strange to people, and in scenes with fast motion, there are some artifacts.

To enable motion interpolation (also called the Soap Opera Effect) set 'TruMotion' to 'User'. For a 30fps source increase the 'De-Judder' slider, and for a 60fps source increase the 'De-Blur' slider.

Frame Hold Time @ 24 fps
27.3 ms
Frame Hold Time @ 60 fps
2.3 ms

The LG SK9000PUA displays 60 and 24 fps content without stutter. The response time of the LCD results in smooth motion even in long panning shots.

24p Judder
Judder-Free 24p
Judder-Free 24p via 60p
Judder-Free 24p via 60i
Judder-Free 24p via Native Apps

The SK9000PUA is able to consistently remove judder from 24 fps content, but is inconsistent in its handling of 60 fps content.

To enable this feature, for any content, the 'Real Cinema' option must be turned on.

Update 05/02/2018: We retested 24p judder over 60p on the SK9000 and it correctly passed the test.

Variable Refresh Rate
Native Refresh Rate
120 Hz
Variable Refresh Rate
G-SYNC Compatible
4k VRR Maximum
4k VRR Minimum
No VRR support
1080p VRR Maximum
1080p VRR Minimum
No VRR support
1440p VRR Maximum
1440p VRR Minimum
No VRR support
VRR Supported Connectors
No VRR support

The SK 9000 does not support any of the variable refresh rates technologies such as G-Sync, FreeSync, or the native VRR which will be available in HDMI 2.1.

Input Lag
1080p @ 60 Hz
15.7 ms
1080p @ 60 Hz Outside Game Mode
36.2 ms
1440p @ 60 Hz
4k @ 60 Hz
15.6 ms
4k @ 60 Hz + 10 bit HDR
23.6 ms
4k @ 60 Hz @ 4:4:4
15.1 ms
4k @ 60 Hz Outside Game Mode
44.5 ms
4k @ 60 Hz With Interpolation
86.2 ms
8k @ 60 Hz
1080p @ 120 Hz
13.8 ms
1440p @ 120 Hz
4k @ 120 Hz
1080p with Variable Refresh Rate
1440p with VRR
4k with VRR
8k with VRR
Auto Low Latency Mode (ALLM)

Excellent low input lag on the SK 9000. Strangely, the input lag is slightly higher on 4k content with HDR enabled (this is the case with the C8 too), but it is still low enough that HDR games will be responsive for most games.

Supported Resolutions
1080p @ 60 Hz @ 4:4:4
1080p @ 120 Hz
Yes (native support)
1440p @ 60 Hz