Results: Pixel Response And Input Lag
To perform these tests, we use a high-speed camera that shoots at 1000 frames per second. Analyzing the video frame-by-frame allows us to observe the exact time it takes to go from a zero-percent signal to a 100% white field.
The pattern generator is placed at the base of the monitor so our camera can capture the precise moment its front-panel LED lights up, indicating that a video signal is being received by the monitor. With this camera placement, we can easily see how long it takes to fully display a pattern after pressing the button on the generator’s remote. This testing methodology allows for accurate and repeatable results when comparing panels.
Here’s a shot of our test setup. Click on the photo to enlarge.
The brighter section of the camera’s screen is what actually appears in the video. You can see the lights of the pattern generator in the bottom of the viewfinder. We flash the pattern on and off five times and average the results.
Here’s the screen draw result.
The 50L7300U has a Game mode, which, as you’ll see below, is necessary. The screen draw time is the same regardless of picture mode. The 240 Hz refresh rate is responsible for that first-place finish. Remember that this is an IPS panel. The only faster screen we’ve tested is the Asus VG248Q, and that TN-based display completed our black-to-white test in only seven milliseconds.
Here is the lag result in the Game mode.
We'd call this a fair result among HDTVs, but it won’t match any computer monitor we’ve tested. And the other picture modes are even slower. In Movie, we recorded a total lag time of 135 ms. Of course, most gamers employing this display will use a console, which is limited to 60 Hz. While the 240 Hz refresh rate reduces motion blur and judder artifacts, players with speedy reaction times will find noticeable input lag in their gameplay.