To perform these tests, we use a high-speed camera that shoots at 1,000 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.
ViewSonic wins the response time comparison by two milliseconds over the others. And although it still lags behind most TN-based monitors, it does show an improvement in IPS technology. Conversely, Samsung trails the pack in this metric. Now, let’s look at the signal lag measurement.
Keep in mind that this is measuring total lag, with the pixel response time factored in. Of course, your actual mileage will vary depending on the hardware and software configuration used. But because we’re using a pattern generator, we can eliminate these variables.
Samsung moves up in the ranking with its lower input lag time. The AOC screen we tested in AOC I2757Fh And ViewSonic VX2770Smh: Two 27" IPS Monitorsis still on top, but the two screens in this review are only slightly behind. When looking at results from the TN-based monitors we’ve tested, we see these latest IPS panels are inching closer in speed. Their response time is within two or three milliseconds, making that comparison a practical wash.
Input lag is generally greater on IPS-based displays, though not by much. Moreover, it's not simply universal that any given TN panel is faster than any given IPS panel. Ultimately, you need to have extremely fast reaction times to be held back by any of these monitors.
- ViewSonic VP2770-LED And Samsung S27B970D
- Test Setup And The S27B970D's Unique Features
- Results: Stock Brightness And Contrast
- Results: Calibrated Brightness And Contrast
- Results: Gamma And ANSI Contrast Ratio
- Results: Grayscale Tracking
- Results: Color Gamut And Performance
- Results: Viewing Angle And Uniformity
- Results: Pixel Response And Input Lag
- Is QHD (2560x1440) Right For You?