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.
Since we couldn’t use our Accupel pattern generator with the HP ZR30w, we employed CalPC Client from SpectraCAL to display a white field pattern. We shot the same video, but this time we recorded mouse inputs to determine the panel’s input lag. Since this method is less precise, we averaged five measurements to arrive at the final value. The DoubleSight DS-309w does accept input from the Accupel, so we measured it like we do our other test screens.
For pure response, both panels are near the top of our comparison. We would expect them to be close since they are both based on similar LG IPS panels.
The real litmus test is the absolute lag metric. This is a function of each monitor’s input control PCB.
The HP is fairly snappy like its 27-inch sibling, but the DoubleSight comes in second to last. As with Auria's EQ276W, I didn’t have any trouble playing fast-paced games, though gamers more skilled than myself might notice the delay. We look forward to testing some high-refresh gaming monitors in the near future, but for now, none of the above screens is really intended for those with super-human reflexes. For the vast majority of people, these 30-inch panels will provide an excellent gaming experience.
