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.
- LG 34UM95 34-Inch Ultra-Wide QHD Monitor Review
- Packaging, Physical Layout, And Accessories
- OSD Setup And Calibration Of The LG 34UM95
- Measurement And Calibration Methodology: How We Test
- Results: Brightness And Contrast
- Results: Grayscale Tracking And Gamma Response
- Results: Color Gamut And Performance
- Results: Viewing Angles And Uniformity
- Results: Pixel Response, Input Lag, And Usability
- LG 34UM95: Solid Performance And Real Usability
Playing on "full" hd (LD? Low definition) feels like a joke once you get to know uhd/4k
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!
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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.
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.
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.
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.
Impressive LOOKING and impressive FUNCTIONALITY are two different things
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
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