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Displays Hardware

Input Lag, Or Why Faster Isn't Always Better 225

Posted by kdawson
from the lag-lag-i-thought-i'd-die dept.
mr_sifter writes "LCD monitor manufacturers have constantly pushed panel response times down with a technique called 'overdrive,' which increases the voltage to force the liquid crystals to change color states faster. Sadly, there are some side effects such as input lag and inverse ghosting associated with this — although the manufacturers themselves are very quiet about the subject. This feature (with video) looks at the problem in detail. The upshot is, you may want to test drive very carefully any display boasting low integer millisecond pixel response times."
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Input Lag, Or Why Faster Isn't Always Better

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  • by morgan_greywolf (835522) on Friday February 06, 2009 @01:21PM (#26755443) Homepage Journal

    These terms 'response time' and 'contrast ratio' are checklist items. What matters is how the display looks and feels. As long as we continue to insist on checklists as a means of determining what to buy, manufacturers are going to keep using tricks like overdrive to make their checklists look better and better.

    At the end of the day, sadly, this means that you can't just look at a checklist when buying an LCD display. You must test drive a model live before considering its purchase.

  • by dk90406 (797452) on Friday February 06, 2009 @01:22PM (#26755451)
    You really should test drive ANY display before you buy it. Or at least read a lot of reviews from reliable sources.
  • by Hyppy (74366) on Friday February 06, 2009 @01:23PM (#26755479)
    Which sucks for people who have very little selection locally. Either buy online, and likely get screwed, or drive a significant distance.

    3rd option: rely on reviews from credible sources. The "credible" qualifier is harder to find these days, though.
  • by fumanchu182 (1428447) on Friday February 06, 2009 @01:24PM (#26755491) Homepage
    Do plasma displays have this same issue?
  • same old... (Score:5, Insightful)

    by apodyopsis (1048476) on Friday February 06, 2009 @01:34PM (#26755647)

    reminds of my time making CDROM drives when we ere chasing 4x, then 8x, then 16x, then...

    never mind the fact that the interface at the time could not handle the high speeds were were getting too so they were totally pointless, the effort was still to physically read some data off the outer edge of the disc at the quoted speed so we could sell the unit and keep up with the arms race.

    I now purposely buy technology a few years old, just so they can work the bugs out and I can ensure it is fully supported under all operating systems, it is rare indeed that I adopt early.

    any technology arms race will promote one specific feature above all others and rarely end up with a device that is fit for market and a well rounded balance of features - though I grant that there are some exceptions.

  • by elrous0 (869638) * on Friday February 06, 2009 @01:41PM (#26755763)
    I've got a LCD panel with 5 ms latency and I don't notice problems when gaming. If you're quick enough to say anything over 1 ms is too slow, you're a pretty hardcore (and quick) gamer. And if you're that good, you're probably best served by a pro setup anyway, not low-level consumer grade shit. But I'm not as twitch quick as I used to be, and my gamertag certainly isn't "Fatal1ty," so 5 ms seems fine to me.
  • by A Friendly Troll (1017492) on Friday February 06, 2009 @01:50PM (#26755883)

    Overdrive is commonly used on all types of panels - TN, *VA, *IPS.

    It isn't related to input lag as much as the summary would like you to believe. Somewhat, yes, but not that much; also, PVA panels are generally the ones with biggest input lag.

    Some *VA panels have an input lag of 3-4 frames, some have only 1; some TN panels have a lag of 1 frame, some have 3. Some panels have overdrive that you cannot even notice, some - like the Dell 2407WHP-HC - will make you want to poke your eyes out.

    What's much worse than input lag and ghosting are the eternal marketing races for MOAR BRIGHTNESS!!!11 and MOAR GAMUT!!1ONE, eventually leaving you with a monitor with a *minimum* brightness of 250 cd/m2, happily roasting your eyes out in anything but daylight, and with a gamut so large that skin tones heavily shift towards red, wildly inaccurate colours, and easily-visible fringing when you turn ClearType on (surprisingly, Windows Se7en will have proper low-level wide gamut management and will tone it down to sRGB on request, eliminating all issues; probably one of the few things that are actually good enough in that OS).

    When it comes to monitors, HardForum is generally the place you want to thoroughly check out: http://www.hardforum.com/forumdisplay.php?f=78 [hardforum.com]

  • by Anonymous Coward on Friday February 06, 2009 @01:55PM (#26755955)

    I'm going to call shenanigans on needing a display with faster than 1 ms reaction times. Is a player even capable of reacting on that small a scale? I'd find that hard to believe when the mean best effort reaction time is on the scale of 10^2 ms.

    The people with the best reaction times beat the mean by a magnitude of 100? Really?

    Can a video output even expect to output at 1000 Hz? For context, the max I've seen CRTs cap out at is around 250 Hz for a complete screen draw.

    Let's face it, though, liquid crystals still represent a physical action in response to an electrical stimulation. This action will take time and it's that time that just can't be eliminated.

  • by Mad Merlin (837387) on Friday February 06, 2009 @02:03PM (#26756057) Homepage

    Then go with a large brand name, and get a common model.

    That's terrible advice, common LCD models are junk, as they're all 6-bit TN panels.

    Most people buy the cheapest LCD they can find in the size they want when they go shopping for one. If you actually want a good LCD, it's becoming extremely hard to find them because junk TN panels have totally flooded the market, and nobody advertises what type of panel their monitor uses.

    Oh, and you wanted a good LCD on your laptop? Forget it, they don't make them anymore.

  • by Bobtree (105901) on Friday February 06, 2009 @02:09PM (#26756135)

    This is one of the reasons why I refuse to buy LCDs for gaming, both on my desktop and for consoles. Other factors include refresh rates, variable resolution, and numerous quality problems (dead or stuck pixels, color reproduction, viewing angle, brightness uniformity, etc).

    Given a choice, nobody would prefer to play on a laggy ISP, so it's really awful that manufacturers don't inform about multiple-frame image processing delays on 60hz monitors.

    CRT technology is so mature and LCD so comparatively half baked that I'm totally revolted by the general consensus to throw out completely superior performance in favor of smaller form factor (it's not like they're moved often).

    I spent months last year looking for a flat panel to buy that I would want to game on, and came up empty handed, so I simply abstain.

    I'm currently using a ViewSonic P220f from a friend after my 8 year old Sony GDM f500r was recently retired, both 21". My consoles are on a 34" Sony WEGA KV-34HS510.

    When my tubes finally give out in a few years, I'll be looking for something far better than LCDs to replace them with.

  • by olddotter (638430) on Friday February 06, 2009 @02:13PM (#26756205) Homepage
    If you aren't a serious game or video editor this probably doesn't matter. I recently bought a new LCD [blogspot.com] for a dirt low price. Some of its specs are unbelievable (possibly with good reason) like the 15,000 to 1 contrast ratio. It claims a 5ms response time. I haven't tested it like CNET would, but I have seen no problems and am very happy with it.
  • OLED to the rescue (Score:5, Insightful)

    by Twinbee (767046) on Friday February 06, 2009 @03:28PM (#26757145) Homepage

    Ugh, input lagging. To me, this would be an even worse issue than blurring or flicker. Lagging (at least above 30ms) means a 'soupy' cursor, and an end to games which require quick reactions.

    I hope this becomes another stat to put on advertising. It's very hard to see unless you hook up a computer and do some testing, so joe public won't care... :(

    It's exactly this kind of thing which will make OLED technology win in the end. All the problems associated with LCD (response time, blurring, lagging, contrast levels) will be gone in an instant.

  • by HalWasRight (857007) on Friday February 06, 2009 @08:17PM (#26760445) Journal

    It's not stuck with a fixed, native resolution like LCD or Plasma displays are.

    Right. Ever heard of an Aperture Grille [wikipedia.org] or Shadow Mask [wikipedia.org]? Apparently not.

  • by Anonymous Coward on Friday February 06, 2009 @09:17PM (#26760919)
    Uh huh. So you're claiming that your timing is PERFECT down to 1/500th of a second. And instead of using this absolutely AMAZING and UNHEARD OF innate ability that even the best drummers in the world don't have, you're wasting your time playing Rock Band. (And this is coming from a drummer of 20 years who enjoys playing Rock Band.) If I were to hazard a guess, I'd say the differences have more to do with the slight variability that you'd get when you play a 3 or 4 minute song two different times. Unless you're claiming to be able to play the same song with absolute perfect timing twice in a row - again with better than 1/500th of a second precision.

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