LCDs images delayed compared to CRTs ? Yes !One, then two and three e-mails arrived this year creating a rumour: LCDs are slower than CRTs in displaying images. If this could be verified, it would be a new strong argument for gamers to stick to CRTs. We started with a practical test of playing with two monitors in clone mode on a CRT Mitsubishi and the superb LCD Dell 2407WFP. To be honest, we would have sworn that synchronisation was perfect, at least at first glance. We replayed the scene, looked a little closer and one thing disturbed us. It was probably just us but the tube monitor seemed to be a little ahead of the other.
We grabbed a Canon digital camera. They are of interest, because the framerate of their videos is 30 images per second and half the frequency of the monitor. The video confirmed our impression that sometimes monitors are synchronous, sometimes the Dell is one to two images behind (with 30 fps for the camera or probably two images compared to the monitor frequency).
We will see however below that the delay considerably changes from one monitor to another. We measured this for all the types of technology we have in the office; TN 2 and 3 ms, IPS 6, 8 and 16 ms, MVA 8 ms. Delays are variable but there are some LCDs that are nevertheless almost as fast as CRTs.
The delay in practiceWe have our video with the CRT on one side and the Dell on the other. Here is what we saw:
Up until this moment everything is fine...
Most of the time, cloning is perfect. And then there are other times…CRT is a little bit ahead
The lag is clearly shown in this picture. The image on the left (the CRT) shows that the opponent has centred shooting, whereas on the right shooting is still oriented on the side. Most of all, however, on the Mitsubishi monitor we have 110 bullets left in the magazine and on the LCD, 111.Well, where do I shoot?
Where is our opponent? In the middle or on the left? To be honest this type of situation is rare and doesn´t last long. It does happen, however. For a normal gamer this won´t be a problem, but if you are a ”professional”, this might be a bit of a problem. Fortunately, there are other faster LCDs.
Also, with a CRT we realise a little earlier that someone is shooting at us. The time gap isn´t that significant, but it is a little behind – and in consequence reaction time is a little longer on LCDs.
An additional stress factor in action scenes
This introduces another factor: the stress level won´t be the same for both monitors. Sound is independent from the display. With CRTs, noise and image are perfectly synchronous. With LCD, the noise will be at best at the same time as the image and at worst one or two images early. We found LCDs that are always two images behind.
We asked the opinion of a sound engineer in the movie business, who explained that this is something they look out for in movies. If the sound comes after the image, this diminishes the stress level of the scene. If it arrives first it increases it. For games, this means that you will hear shots slightly before seeing them. You won´t necessarily be aware of it, but our brain will…and it will generate a slightly higher level of stress. So be aware if you are looking for a scary experience, we suggest you to buy a LCD monitor with a maximum of delay.