LCD response times do NOT equate to decreased ghosting...

[BalAtWork]

Here is the quote from the Samsung LCD engineer at CES

Total response time = Rise time + Fall time. Rise time sends the full electrical signal to the pixel and produces white. The electricity is stopped and then the pixel falls to black. The problem with the measurement is that pixels on TV's rarely move from full white to full black. There is another measurement though (I forgot what he called it) that is how long it takes a Pixel to shift from one color to another and that is almost always longer. It has to do with sending a non-full signal to the pixel and the fact that the "energizing" of the pixel at non-max can be significantly longer than when going to white/black. This is why posted response times on computer LCDs never seem to have bearing on gaming ghosting (except to be someone directional) and those with a higher response time can actually seem to have less ghosting.

Here is the link to the AVSforum original thread. They are discussing the new 54" LCD displayed at CES this year.

AVSForum original thread (page 2)

Companies have discovered ways of compensating for these color switched taking longer such as LG/Philips "overdrive" they currently use in their 52" LCD.


I only post this because so many people here just rattle off what they are told that response time is everything. It is an indicator, but a poor one at that. I was tired of people telling other "not" to buy the LCD at Walmart due to its higher response time (see Hot Deals). They never even had the gall to see the unit before condemning it (even though users reported NO ghosting to minimal).

 

[Bovinicus]

This is very true. FFD technology aims to decrease the more realistic switching times of color to color. Once this technology hits the market (Any year now...) ghosting will be a thing of the past, in theory. If companies averaged the all possible switching times together it would be a much more useful indicator. Maximum, minmum, and the standard deviation of switching times would be very helpful as well.

 

[BalAtWork]

I knew the technology was on the way, but never read enough of the design docs to understand it was aimed at the signal strength like it is. I agree with you on the average time versus the extreme. Trust the big business to find the numbers that make them look the best regardless of any real world application of their stats.

 

[JKing76]

There have been tons of discussions here about Feed Forward Driving (most recently, a resurrected thread New LCD Technology Shipping in November, and various ones about the 16ms response Hiatachi and Planar panels).

Traditional response time is measure in terms of the Full Black -> Full White and Full White -> Full Black times, probably because that *used to be* the fastest responses. Things like FFD use the full voltage differential of the Full X -> Full Y to do the partial transitions, so now they are the fastest. Maybe new response times will be given in terms of the average of all transitions?

Anyway, faster response time DOES equate to decreased ghosting. It's just that the FULL response rate involves more than Black->White and vice versa.

 

[BalAtWork]

Thats true...as I said it is an indication. But due to the inherent design of the partial signal in current models, that response time of black to white is now the shortest instead of the longest. It is a poor indication due to the fact that a monitor with a response time of 25 ms may have a response time of 40 ms for a color transition. Meanwhile, a monitor with a 30 ms transition may have a 35 ms color transition time. Hence the higher response time LCD will have a lower ghosting effect.


Just an example, and without stats on the LCD's, there is no way to tell except subjective visual judgement.

 

[thraxes]

That's I have been telling peopole who want to buy a TFT off me for the last year or so: Go look at it in a store and if you like it come back to me for a better price

For Monitors there is nothing like giving one a good test drive, be it TFT or CRT, try before you buy and don't let specs blind you (example: some monitors have good specs, but at higher resolutions some cheaper crt models tend to have a moire effect).