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Measurement And Calibration Methodology: How We Test

Asus VG248QE: A 24-Inch, 144 Hz Gaming Monitor Under $300
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To measure and calibrate monitors, we use an i1Pro spectrophotometer and version 5.1.2 of SpectraCal’s CalMAN software.

For patterns, we employ an AccuPel DVG-5000 video signal generator. This approach removes video cards and drivers from the signal chain, allowing the display to receive true reference patterns. Connections are made via HDMI.

The AccuPel DVG-5000 is capable of generating all types of video signals at any resolution and refresh rate up to 1920x1080 at 60 Hz. It can also display motion patterns to evaluate a monitor's video processing capabilities, with 3D patterns available in every format. This allows us to measure color and grayscale performance, crosstalk, and ghosting in 3D content via the 3D glasses.

The i1Pro is placed at the center of the screen (unless we’re measuring uniformity) and sealed against it to block out any ambient light. The Accupel pattern generator (bottom left) is controlled via USB by CalMAN, which is running on the Dell XPS laptop on the right.

Our version of CalMAN Ultimate allows me to design all of the screens and workflows to best suit the purpose at hand. To that end, we’ve created a display review workflow from scratch. This way, we can be sure and collect all the necessary data with a concise and efficient set of measurements.

The charts show us the RGB levels, gamma response, and Delta E error for every brightness point from zero to 100 percent. The table shows us the raw data for each measurement. And the area in the upper-left tells us luminance, average gamma, Delta E, and contrast ratio.
 

Every primary and secondary color is measured at 20, 40, 60, 80, and 100 percent saturation. The color saturation level is simply the distance from the white point on the CIE chart. You can see the targets moving out from white in a straight line. The further a point is from center, the greater the saturation until you hit 100 percent at the edge of the gamut triangle. This shows us the display’s response at a cross-section of color points. Many monitors score well when only the 100 percent saturations are measured. Hitting the targets at lower saturations is more difficult, and factors into our average Delta E value (which explains why our Delta E values are sometimes higher than those reported by other publications).

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  • 3 Hide
    CaptainTom , October 2, 2013 10:04 PM
    I gotta wonder if 1 ms vs 5 ms really makes a difference...
  • 4 Hide
    ff6shadow , October 2, 2013 11:45 PM
    I own this. Bought when it was first available. Great monitor for gaming. I use 2x GTX Titans with it.
  • -7 Hide
    iam2thecrowe , October 2, 2013 11:56 PM
    i don't like the sound of this dithering BS, i guess that's why its cheap....
  • 1 Hide
    SWEETMUSK , October 3, 2013 12:08 AM
    if I have $300 dollars I will not buy for 24 inch "TN" screen
    IPS is much better then TN
  • 0 Hide
    Axonn , October 3, 2013 1:37 AM
    People who think 144 Hz is more important than an 8-bit panel are in for a big, big fail.
  • 4 Hide
    ryude , October 3, 2013 2:03 AM
    This monitor uses PWM (Pulse Width Modulation) for the backlight, which causing flickering. The only 144hz monitor that does not use PWM is the BenQ XL2420TE.
  • 2 Hide
    Plusthinking Iq , October 3, 2013 2:25 AM
    they only sell BenQ XL2420T version in my country, so i bought the asus for the double pwm hz. pwm, the scourge og the lcd monitor.
  • -1 Hide
    CraigN , October 3, 2013 5:07 AM
    ryude - yes, it uses PWM, however, as an owner of one of these monitors, I have not noticed any flickering at all. It's a really solid performing monitor. That same PWM comes in real handy when running in Lightboost mode for even more reductions to input lag.

    CaptainTom, 1ms makes a huge difference over 5ms. I didn't think it would at first until I bought one of these. Next to my old 24" HDTV that was my monitor for awhile, the difference is insane.

  • -1 Hide
    CraigN , October 3, 2013 5:08 AM
    PS , Christian, your SmartBuy award photo at the end of the article is the wrong ASUS monitor ;)  Also, would you guys mind releasing the ICC profile you guys calibrated for your tests?
  • -1 Hide
    Turik , October 3, 2013 5:11 AM
    The final picture is not of the VG248QE?
  • 0 Hide
    Turik , October 3, 2013 5:13 AM
    As someone with a high quality 1440p IPS and 2 of these monitors, for most gaming I prefer these. For World of Warcraft or other MMOs where screen space is a luxury, it's hard to give up the high-res IPS, and the color quality is noticable, but with a proper ICC profile and some tweaking, it's a good looking monitor.

    ICC profile is use is here: http://pcmonitors.info/reviews/asus-vg248qe
  • -4 Hide
    ubercake , October 3, 2013 5:17 AM
    The thing is contrast is lacking big time on IPS monitors less than $500. So who cares about color accuracy if you can't see all the shades? Cheap IPS monitors are not only slow because of inherent input lag, but also a fail when it comes to contrast.

    These high refresh rate monitors offer an incredible performance boost for first-person shooters if you have video cards that can produce frame rates close to the high refresh rates (or higher than 60Hz consistently). I've tried 1440p 60Hz monitors and can't stand the lower refresh. I've tried 60Hz surround setups and can't stand the low refresh. Once you go to these monitors, you develop a need for them. Nothing with lower refresh rates compares any longer. If you've never had it, you don't miss it and don't know what you're missing.

    If you don't have the kind of GPU power to consistently get you beyond the 60fps mark at 1080p, 60Hz monitors are the way to go. I still wouldn't settle for cheap IPS monitors with crappy contrast ratios though. For shooters, the input lag is also a terrible characteristic of the cheap IPS monitor.
  • 0 Hide
    finder , October 3, 2013 5:27 AM
    and it's backlight flickering as hell https://www.youtube.com/watch?v=sBYnnBfub4E&mode=post-play
  • 5 Hide
    twztechman , October 3, 2013 5:43 AM
    Quote:
    I own this. Bought when it was first available. Great monitor for gaming. I use 2x GTX Titans with it.


    2 Titans for 1980x1080 resolution? That's a bit silly. You have spent $2000 for video cards and you are gaming on one 1980x1080 24 inch monitor!
    You should have at least 3 of these monitors for a surround set-up.
  • 0 Hide
    CraigN , October 3, 2013 5:47 AM
    Turik - I'm aware of the one at pcmonitors.info, as well as the one included with the disk. I was just wondering if it was (possible) for them to release their post-calibrated icc. I have no idea how monitor calibrators work (I didn't need to alter much on my personal VG248QE to be satisfied, but that doesn't mean it couldn't be better) so I just thought it couldn't hurt to ask.

    Also - does anyone own one of these and notice that opening Pictures come up darker/dimmer than they look as thumbnails or in image preview??
  • 8 Hide
    BigMack70 , October 3, 2013 5:57 AM
    I just wonder if/when we'll ever get a panel like this at high resolution (1440p/4k), because I'm done with 1080p.

    ASUS... could you pretty please make us a 144 Hz 1440p IPS screen ??????
  • 7 Hide
    ubercake , October 3, 2013 6:06 AM
    Quote:
    I just wonder if/when we'll ever get a panel like this at high resolution (1440p/4k), because I'm done with 1080p.

    ASUS... could you pretty please make us a 144 Hz 1440p IPS screen ??????


    I second the 'pretty please'.
  • 0 Hide
    moogleslam , October 3, 2013 6:48 AM
    If I understand things correctly, if your monitor updates faster than the frame rate pumped out by your graphics card, you don't have screen tearing anymore, and therefore no longer need vsync?
  • 0 Hide
    jdon , October 3, 2013 6:51 AM
    I've looked at IPS panels and TN panels in some depth, and found that other than the viewing angle, I'm not able to perceive much difference. Then my fiancee laughed at me and said, "You really are THAT colorblind, huh?" ....It actually kind of makes me glad that I can appreciate the better frame rates without being disappointed by the lack of color depth!
  • 3 Hide
    vpnuser , October 3, 2013 7:02 AM
    I own one of these as well as a 27" Dell 1440p IPS panel, and I prefer this one for gaming. 120hz with 2D lightboost has 0 ghosting. Sure the color is crap compared to the IPS, but what good is color when it looks like 24fps movie blur in games? Quoted from my girlfriend, who can't tell the difference between 1080p and 720p movies, within 5 minutes of me setting up the monitor ; "That's really smooth."

    I would prefer the best of both worlds, but I don't think current graphics cards are quite up to the task. (At least not for less than a $2500 machine) Current IPS panels out there can pull the hz, but can't match the response times just yet.

    Add in the fact that the industry will be pushing for 4k soon, and you can kiss 120hz goodbye for a while.
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