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Response Time: 60Hz

I measured the SyncMaster 2233RZ’s response time in two modes: at a refresh rate of 60Hz and 100Hz. 60Hz goes first.

This is a typical result of a TN matrix with response time compensation. The response time average is 3.2 milliseconds (GtG), which agrees with the manufacturer’s specification. The maximum response is as long as 17 milliseconds, but only on one transition from black to a dark gray. This is a normal behavior of a modern gaming monitor.

The average level of RTC errors is 9.6%. This is not much but enough to make the resulting visual artifacts conspicuous in some situations as I already noticed in the subjective part of the review.

Besides measuring the RTC error in percent, I want to introduce a new measurement, in milliseconds. I’ll explain the point of such a measurement now.

This is a typical diagram of the switching of a monitor pixel from black to gray, recorded with a photo-sensor and oscilloscope. The pixel is black until the 40th millisecond (X-axis) and then it receives the command to change color. The powerful impulse of the RTC circuit changes the pixel’s brightness to necessary level (somewhat higher than 160 units of the Y-axis) in just a couple of milliseconds, but proves to be too strong. As a result, the pixel gets brighter (about 210 units) than necessary. After that, the pixel takes a few tens of milliseconds to get back to the necessary level. During this time the pixel remains brighter than necessary as is indicated by the wide and high hump in the graph. This hump shows up as bright trails known as RTC artifacts.

Thus, when measured in milliseconds, the RTC error is the relaxation time the pixel takes to really deliver the desired brightness. This effect is different from response time proper in its origin and visual appearance, so I won’t sum the two up.

The picture is quite depressing: the relaxation time average is 15.2 milliseconds which is five times as high as the monitor’s response time average. The maximum relaxation time is as high as 50 milliseconds! This is why RTC artifacts are conspicuous to a naked eye.

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