2ms vs 5ms

John24

John24

John24

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I've read lower response time is better for games/HD but I've also read that different manufacturers calculate response times in different ways.

Is there any measurable difference in real world and is there any point trying to compare this figure between two makes without knowing exactly how said figures were calculated, or will a 2ms be faster than a 5ms monitor regardless of how the figure was calculated? :confused:
 
The rated "ms" is usually some optimum "halftone" metric, like rise-time from 25% to 75% "whiteness", or something like that, depending on what the panel does the fastest. The complete rise and relaxation times are multiple times longer. It's something to do with how the overdrive stuff works, it's quick in the mid-range and slow at the top and bottom end.

Not sure where I read it, but I think normal relaxation times from 100% to 0% is around 10-15ms for TNs, which is only marginally better than the other panels (but good enough for "no ghosting"), while the half-tone speed can still be as low as 2ms for optimal transitions, which is what they put on the box. Relaxation (going from a "forced" state through applied voltage to the natural state) is always a lot slower than the other way around, but it's never stated in the specs.

Which is why a 10ms IPS display can be subjectively just as "ghost free" as a 5ms TN.
 
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So the ms value is at best a very rough guide.

I'm trying to decide between the DELL ST2410 and Samsung SyncMaster P2450H, the Dell would be my preference if it has the same or lower response time/input lag than the samsung.
 
John24 said:
So the ms value is at best a very rough guide.

I'm trying to decide between the DELL ST2410 and Samsung SyncMaster P2450H, the Dell would be my preference if it has the same or lower response time/input lag than the samsung.
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Even as a rough guide, they're pretty bad, the main thing is just a checkbox feature they put on the box to get those who don't have a clue to go "cool, I'll get that one".
 
some info here about it too: http://www.tftcentral.co.uk/specs.htm

Worth noting that a 5ms response time (from a lower budget TN Film panel) is indicative of a panel where response time compensation (RTC - overdrive) has not been used. 2ms response times, and where you see "G2G" figures quoted show that RTC is being used. This is a proven technology for improving a panels responsiveness in practice as well as on paper, so it can give you better results.

You will also want to bear in mind things like input lag, and 60hz vs 120Hz for gaming nowadays
 
So Goofball and kylew are wrong after all then and there is a big enough difference to choose 2ms over 5ms? :confused:

i also have a third option now, a 6ms second hand 2407WFP A04 with 2 years operation time for £180.
 
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If you are talking a 5ms TN Film panel without overdrive vs a 2ms G2G panel with overdrive then yes, I would argue there is a noticeable difference in pixel responsiveness. On the 5ms model the response time quoted is based on the ISO measurement across the black > White transition. Typically the fastest, but all other transitions between diff grey tones are slower. Since it's pretty rare in real use to have a full black > White transition, the response time across intermediate tones is much more important. This is where overdrive technology comes in and the 2ms figure is quoted across grey to grey transitions in the best case.

You can see this in practice as a movin object will show noticeably less blurring and trailing on a model with overdrive. The images in the response time tests at TFT Central and also places like BeHardware / digitalversus show this quite well. If you look at the response time graphs at places like x-bitlabs you will also see this improvement.

In some cases adding overdrive can cause some after effects and artefacts. Some models exhibit characteristic White of black halo-ing behind moving objects but this is on models where the overdrive impulse is poorly controlled and implemented. In most cases it really does help improve responsiveness.

In regards to the 6ms G2G Dell 2407wfp, same principals apply but his is a slightly diff case as it's an S-PVA panel and has diff performance characteristics to start with. Again an overdrive enabled PVA panel will offer much better responsiveness Han one without. In practice a 6ms G2G S-PVA panel is maybe a little faster than a 5ms TN film panel. Have a look at the reviews o the Dell 2407wfp and 2408wfp on TFT Central as they are both 6ms G2G panels and you should be able to make some comparisons against the 5ms TN film models
 
John24 said:
i also have a third option now, a 6ms second hand 2407WFP
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Try to see can you distinguish its ghosting from that of "2ms" TN:
http://www.behardware.com/medias/photos_news/00/20/IMG0020654.jpg
http://www.behardware.com/medias/photos_news/00/17/IMG0017419.jpg
http://www.behardware.com/articles/686-4/review-of-the-dell-2407wfp-hc.html


Baddass said:
In some cases adding overdrive can cause some after effects and artefacts.
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I'ts not just able to cause that but it will cause it the more response time is tried to accelerate because RTC is based to "overshooting" control signal in required direction and if you want to increases response further only way to do that is to increase that overshoot.
Liquid crystals are simply slow and their spec improvements are achieved with this kind of deceits.
 
Why can't screen makers state testing methods, it would make it a lot easyer. ;)

Going to go with the 2ms P2450H now and thanks for the help lads. Appreciated.
 
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