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Samsung PN51F8500 Review: A 51-Inch Plasma HDTV With SmartHub

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.

The F8500 has a game mode that reduces processing to lower input lag. It does not affect the screen draw time, which is already lightning-fast. A plasma panel goes black between frames, rendering motion blur almost non-existent. Even though you’re limited to 60 Hz, that fact contributes to very smooth motion on-screen.

Here are the lag results:

Game mode certainly does improve our input lag measurement. But Samsung's F8500 is still well behind the performance of even a typical computer monitor. If you plan to hook up a gaming PC to a plasma panel, Pioneer's Kuro is a better choice. It’s too bad they’re not made any more! Console gaming shouldn't pose as much of an issue; you can only move and turn so fast with a joystick or directional pad.

One spec that may catch your attention is the F8500’s 96 Hz refresh rate. Unfortunately, the TV cannot accept a 96 Hz signal. For that, you’re still limited to 60 Hz over HDMI. The 96 Hz figure refers to the output rate, which is designed for the proper handling of 24p content, where each frame is repeated four times. If you turn on frame interpolation, you can enjoy smoother motion in games, though you might see the occasional tear.

Christian Eberle is a Contributing Editor for Tom's Hardware US. He's a veteran reviewer of A/V equipment, specializing in monitors.