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Results: Grayscale Tracking And Gamma Response

LG 34UM95 34-Inch Ultra-Wide QHD Monitor Review
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The majority of monitors, especially newer models, display excellent grayscale tracking (even at stock settings). It’s important that the color of white be consistently neutral at all light levels from darkest to brightest. Grayscale performance impacts color accuracy with regard to the secondary colors: cyan, magenta, and yellow. Since the 34UM95’s CMS can’t correct all color gamut errors, accurate grayscale is key.

LG's 34UM95 is set to its Custom picture mode by default. The resulting un-calibrated grayscale is just a tad cool. The error is barely visible and only at the 70- and 80-percent levels. Out-of-box performance is definitely above average.

If you don’t plan to calibrate, we recommend using the Photo mode instead.

As you've seen, the Photo mode offers a little more light output and its grayscale accuracy is about the same as Custom. You still have access to Brightness, but the Contrast and Color controls are locked out. The errors are visible at the 70- to 100-percent levels, showing just a hint of green. We still consider this above-average performance.

Here is our calibrated result:

Calibrating the Custom mode yields the best grayscale accuracy. You give up around 20 percent of the available contrast, so some users might opt to leave the RGB sliders and/or the Contrast control alone and simply adjust Brightness to taste. Either way, we expect you’ll be satisfied.

Here is our comparison group:

An average error of 2.37 Delta E is comfortably below the visibility point. Most brightness levels have no visible error at all. The ones that do will take sharp eyes to detect.

Calibration puts the 34UM95 on par with many professional displays.

It’s hard to find a monitor much more accurate than this. We think the compromise in contrast is worth such an excellent result. Since we were unable to try out the automatic calibration, we can’t say whether it's possible to get even better numbers. Visually, however, you wouldn’t be able to tell the difference.

Gamma Response

Gamma is the measurement of luminance levels at every step in the brightness range from 0 to 100 percent. It's important because poor gamma can either crush detail at various points or wash it out, making the entire picture appear flat and dull. Correct gamma produces a more three-dimensional image, with a greater sense of depth and realism. Meanwhile, incorrect gamma can negatively affect image quality, even in monitors with high contrast ratios.

In the gamma charts below, the yellow line represents 2.2, which is the most widely used standard for television, film, and computer graphics production. The closer the white measurement trace comes to 2.2, the better.

LG's 34UM95 has three gamma presets, but all of the charts we’re showing represent the Gamma 1 option. Our intent is to illustrate the difference between the Custom and Photo modes, along with the impact of Black Level.

You can’t change the gamma in Photo mode, so you’re stuck with tracking shown above. Luminance errors become brighter as you move towards 100-percent brightness. In actual content, the image lacks a little depth compared to one with a flatter gamma trace.

In Custom mode, you have a choice of High or Low for the Black Level control.

The differences are subtle. However, set to High, the trace stays below 2.2 throughout the entire brightness range. At 90 percent, the error maxes out at 4.1 cd/m2, which is barely visible.

We think image quality is superior at the Low setting.

I realize it's only a small change, but I can really tell the difference looking at actual content. The error starts a little too dark and slides under the line at the 40-percent mark. Now the maximum error is 3 cd/m2.

Here is our comparison group again:

The average of our tested monitors is about .27. LG's 34UM95 doesn't demonstrate the flattest tracking we’ve seen, but it’s pretty close to our standard.

We calculate gamma deviation by simply expressing the difference from 2.2 as a percentage.

The 34UM95’s deviation result is a good deal better than average. Gamma 1 with the Black Level set to Low definitely produces the best numbers in our gamma tests.

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  • 6 Hide
    InfinityPixels , July 25, 2014 12:30 AM
    I want this so bad.
  • -7 Hide
    rantoc , July 25, 2014 3:20 AM
    4k gaming is amazing but demand alot from the computer hardware. Just got a dell 3214 and its hard to describe how much better the picture/emersion is with the way higher definition in the picture quality and still came from descent 2560x1600 before that.

    Playing on "full" hd (LD? Low definition) feels like a joke once you get to know uhd/4k
  • 2 Hide
    wtfxxxgp , July 25, 2014 3:33 AM
    Rantoc, what does your comment have to do with the article? Seems to me that you were waiting for an opportunity to brag about your new monitor... Glad you got that out of your system. lol

    With regards to this monitor...I LOVE the looks...very elegant. I think the price tag is fitting as well - it has great resolution and there are still plenty of people who are gaming on 60hz displays that may have just enough GPU power to actually game at this thing's native resolution, albeit with slightly lower settings. GG LG!
  • 8 Hide
    ubercake , July 25, 2014 4:30 AM
    Great to see larger-sized higher-than-HD res monitors.
  • 1 Hide
    Nossy , July 25, 2014 5:39 AM
    For a grand, you can get two Asus PB278Q.
  • -1 Hide
    cknobman , July 25, 2014 6:50 AM
    $1000?

    Next
  • 1 Hide
    xPandaPanda , July 25, 2014 9:43 AM
    I have this monitor. Because of it's cinema format, market age, lower production numbers, and early adoption as competitors haven't offered this yet, it is reasonable to think this monitor would cost this much--a lot.

    It would have been nice to include what revision this is, because LG is aware of uniformity issues, which is why the product was largely on backorder and a Rev.2 is in place (but Rev. 2 didn't fix the problem either). My first one had a glaring Uniformity problem, but LG is cool and offered an advanced exchange. The new one has some uniformity problem, but it is very 'livable' and discrete.

    Overall, I am pleased with this product. I have a single 780 to push this and it works nicely. If I got a 4k monitor, I'd have performance issues as the GPU as a whole sector is behind.

  • 6 Hide
    eklipz330 , July 25, 2014 12:09 PM
    as a pc gamer who has been playing for ~15 years, i have to say that this is one of the biggest changes that i've seen on the pc platform. this is a big step towards bringing pc back to relevancy. it's something that will be held to acclaim in productive and gaming environments. in fact, the only thing that i'm surprised that they didn't do is make it curved, simply because when a user sets up a multi-monitor setup, they set the outside monitors at an angle. this makes curved monitor solutions make sense more so than tvs, especially since curved monitors benefit solo users the most. im shocked they didnt make it curved. probably going to cash in next year on that.

    seriously though, pc monitors have been lacking for some years now, falling behind in innovation and technology in general(phones have been jacking up their screen quality year after year, we've been stuck since like 2005). i bet 21:9 screens will have the biggest penetration on PCs.
  • -1 Hide
    josejones , July 25, 2014 1:48 PM
    Why still the old HDMI 1.4 instead of HDMI 2.0 and DisplayPort 1.2 instead of the new 1.4 ???
  • 0 Hide
    Jamie Blumenfeld , July 25, 2014 3:24 PM
    Wish this was 1600 pixels tall. Don't get the fascination with XX:9 at all.
  • -2 Hide
    mikeangs2004 , July 25, 2014 4:34 PM
    don't post spam
  • 0 Hide
    Phillip Wager , July 25, 2014 8:56 PM
    i want this bad its a good compromise of between high framerate and high pixel count. honestly for gaming i would just run 2560x1440 but i would run the full resolution for the desktop
  • 1 Hide
    SessouXFX , July 26, 2014 10:14 AM
    This monitor...it's been at the top of my list for nearly a month now. I know most gamers would prefer to see something with a better aspect ratio, and certainly better response and refresh time. But if you use your monitor for more than gaming, say watching movies, streaming on twitch, and using multiple applications at a time, I'm not sure how you can ignore it as a possibility.
  • 0 Hide
    photonboy , July 26, 2014 1:45 PM
    21:9 ->
    This is simply a horrible aspect ratio for most people.

    The problem is that if you can see the entire monitor without moving your head then 16:9 is the proper ratio to maximize viewing area such as 3840x2160.

    Ultrawide really only makes sense if it's WIDER than what you can see without moving your head. For that, I'd rather have more than one monitor.

    Ultrawide for gaming makes little sense. Screens need to be curved, or have multiple angled monitors with minimal gap but a single super-wide screen just doesn't work.

    *If you really think about it, it's hard to justify the 21:9 ratio.
  • 2 Hide
    SessouXFX , July 26, 2014 2:36 PM
    Quote:
    21:9 ->
    This is simply a horrible aspect ratio for most people.

    The problem is that if you can see the entire monitor without moving your head then 16:9 is the proper ratio to maximize viewing area such as 3840x2160.

    Ultrawide really only makes sense if it's WIDER than what you can see without moving your head. For that, I'd rather have more than one monitor.

    Ultrawide for gaming makes little sense. Screens need to be curved, or have multiple angled monitors with minimal gap but a single super-wide screen just doesn't work.

    *If you really think about it, it's hard to justify the 21:9 ratio.

    Don't knock it, if you haven't tried it. Seen the demos of this screen with 21:9, it's quite impressive looking, compared to the other ratios out there. At the very least, it's more compelling than given credit for.
  • 0 Hide
    Home-World , July 27, 2014 9:33 AM
    What to see the same density as 4k, the ultra wide is the way forward for me buy one instantly
  • 0 Hide
    moogleslam , July 27, 2014 12:53 PM
    This size/format needs G-Sync and a faster refresh rate, then it would be perfect for my gaming needs.
  • 0 Hide
    somebodyspecial , July 27, 2014 5:49 PM
    Next time, ask for an ULTRA TALL monitor. So we don't have to scroll too much. You know, just get back to 2560x1600. 1440p sucks and going further with width doesn't help my browsing etc. There's a premium on 1600P right now just because of all this 1440p crap taking over. How many people are using spreadsheets all day? Some width is ok but I'd rather have tall and more monitors to get more width (2 or 3 screens) vs. splitting crap on one HUGE wide screen. Give me 2 or 3 1600p 27/30inchers and I'd be happy to drop different apps on each or run games.

    Impressive LOOKING and impressive FUNCTIONALITY are two different things ;)  I'm not saying wide isn't good for SOME applications, but not for the majority of us. Not sure where monitor makers are getting their data, but I don't think they're asking the right people what we users want :) 
  • 0 Hide
    ubercake , July 28, 2014 5:24 AM
    ...

    Quote:
    This size/format needs G-Sync and a faster refresh rate, then it would be perfect for my gaming needs.


    That's what I'm thinking. It seems like the wider the screen resolution the more perceivable tearing is. G-sync would help this situation. Acer is supposed to be releasing a 4K G-sync monitor in the next 6 months or so:
    http://www.geforce.com/whats-new/articles/nvidia-g-sync-monitors-unveiled-shipping-soon-worldwide
  • 0 Hide
    dehcbad25 , July 29, 2014 11:29 AM
    I had the 29UM95, and I am writing from that monitor. Christian...WHAT USERS WERE COMPLAINING ABOUT THE SIZE? I can buy 2 29UM95 for the price of 1 34UM95.
    Granted the 34" will have its uses and applications, but from the UWHD I don't think it will be the most sold. the 27" might be too small, but 29" is perfect for 2650x1080. BTW, I do game in this monitor too, and I work on it TOO
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