Reaction time tests
A car moves from left to right at high speed.
Movement isn’t perfectly fluid. Depending on its speed, the car is shown in several successive positions. If the car goes very fast, the positions are very close and the eye perceives a flowing movement. Perfect monitor monitor with 3 ghost images
A monitor without ghosting effects would have previous images completely fading away when a new one appears. This is the theory and in practice, it´s often not the case as images progressively fade. Sometimes up to 5 afterglow images remain on the monitor and represent the visible white trail behind objects. Some monitors have strong overdrives in addition to image anticipation algorithms. In this case, an image can appear in front of the main object, creating a white halo ahead of objects in motion.
With CRTs we captured afterglow with a camera at a shutter speed of 1/60 seconds as compared to 1/1000 s for an LCD. We take 50 pictures per test. We then can see a monitor’s ghosting effects, or all the car’s position in the entire process. The most important image is the one on the left, the better one. It will be the most displayed on the monitor, while the one on the right is in transition.
Here are the two extreme states with each monitor as afterglow oscillates.TN 5 ms : Acer AL2216W
TN 2 ms : Asus MW221u
19" : TN 2 ms, BenQ FP93G X
TN 5 ms : Belinea 2225 S1W
TN 5 ms : Fujitsu-Siemens L22-1W
TN 5 ms : HP w22
TN 5 ms : Samsung SyncMaster 225BW
20" : TN 8 ms, BenQ FP202W
We added two reference monitors to the six 22" monitors tested: a 19" TN 2 ms and a 20" TN 8 ms. This was quite useful and simplifies the interpretation of results.
The Asus MW221u, the only 22" 2 ms, is as good as the BenQ FP93G X, the fastest 19" (except for 100 Hz monitors). The BenQ is as good as the other 2, 3 and 4ms but we had to pick one.
The most interesting point is that the Asus doesn´t have an AU Optronics panel as we thought it would have, or a Samsung . Nor is it a LG Philips. It’s a Chi Mei Electronics or CMO. This result is surprising as we were used to seeing low quality panels (with high response times) from this manufacturer.
We have to say that this is a tremendous improvement and CMO is now much ahead of other 22"s. Their product is comparable to the previous generation of TN 8ms monitors (as the picture of the BenQ FP202W shows). The latter didn´t represent a huge improvement compared to previous TN 16ms.
In games the difference is obvious and the Asus is much faster than other monitors. It is much less subject to afterglow, the blur effect resulting from character movement or the credits at the end of a movie.
As for the other five, they are equivalent. This isn´t a catastrophe but you shouldn´t expect extraordinary reaction time in games and it isn’t comparable to CRTs. There will be some blurring but if you don’t look for it, it’s unnoticeable.
Our next section should be titled, The revenge of the slow monitors!