Picture Quality

The KTC H27T22 features an AU Optronics 8-bit Fast IPS panel capable of displaying 16.7 million colors. The panel can, in fact, be pushed to display 10 bits of color per channel by using Frame Rate Control (FRC), a method of temporal dithering, to create a perception of 1,024 individual shades of RGB color (1.07 billion colors in total). Unless you're a creative professional with an established end-to-end 10-bit color workflow, you shouldn't lose sleep over the 8-bit+FRC nature of this monitor.

The monitor uses an edge backlight unit controlled by direct current (DC). That makes the monitor flicker-free at any given brightness level. The screen coating on the KTC H27T22 is light anti-glare (AG). The screen is quite resistant to reflecting its surroundings even when used in a room with a lot of natural or artificial light, and the picture isn't perceived as grainy or dirty from a normal sitting distance, which can be the case with heavier AG coatings. The maximum specified brightness of the panel is 300 cd/m², accompanied by a static contrast ratio of 1,000:1.

To test the picture quality of the KTC H27T22, I've used a combination of the X-Rite i1Display Pro and DisplayCAL, a powerful software solution for display calibration and profiling which is completely free to use, assuming you own a supported colorimeter.

Picture Quality at Factory Settings

The picture quality of the KTC H27T22 at its factory defaults was tested right after plugging the monitor in and allowing the panel to warm up for about an hour. The out-of-the-box picture tuning strikes me as somewhat conservative, as the brightness is set to only 40 in the OSD, which results in an actual panel brightness of 171.6 cd/m². The colorimeter also showed a reasonable contrast ratio of 870:1 but with a noticeable white point deviation; instead of 6,500 K, the white color temperature was 6,381 K on the review sample of the monitor, with the Color Temperature set to Warm by default.

Subjectively, the picture looks good, although definitely too dark, more so during daytime. The sharpness of a 27-inch 2560x1440 panel is excellent, and there's enough screen real estate to work in two windows at the same time without having to zoom out to the point of discomfort.


The measured out-of-the-box gamma had an average value of 2.31, which could be better, as we want it as close to 2.2 as possible. The measured gamma curve reveals even more issues than the number implies; just look at the left part of the graph, where the gamma is significantly higher than it should be, resulting in crushed blacks and lost details in dark parts of a scene, as the shadows are interpreted as darker than determined by the input signal. The situation greatly improves past the 50% level. Unfortunately, while the monitor offers various gamma settings (Off, 1.8, 2.0, 2.2, 2.4), none of them are any better than the default (2.2) so it's not worth changing this setting in the OSD. The only way to properly fix gamma is with software calibration of the monitor.


As for the color accuracy, the out-of-the-box ΔE on the review sample of the KTC H27T22 is 2.48, with the maximum ΔE climbing up to 4.64. The gray tones are very accurate, but the colorimeter caught some substantial inaccuracies in red and blue color tones.

Before moving forward, I looked for the best manual panel settings. By adjusting a couple of options in the OSD, I was able to significantly improve the contrast ratio, fix the color temperature, and even gain some improvements in color accuracy. The main area of focus is Color Temperature, found in the Color menu. For best results, I had to set it to User and then manually adjust the color channels to 46 (Red), 48 (Green), and 50 (Blue). The only other thing I had to do was increase the brightness (Display menu). I prefer around 250 cd/m² for combined day and nighttime usage, which I was able to hit after setting the Brightness to 43. Let's take a look at what happened after those tweaks were conducted.



With our minor tweaks, we improved almost every aspect of the picture quality, most notably the color temperature and contrast ratio. For further improvements, calibrating the panel is necessary.


In terms of color gamut, the KTC H27T22 actually goes beyond its official technical specifications. I measured a 99.9% coverage of the sRGB and a 94.6% coverage of the DCI-P3 color space with the aforementioned adjusted settings. The gamut volume equals 137.7% for sRGB and 97.5% for DCI-P3 color spaces, respectively. For an affordable gaming monitor, these are commendable numbers indeed.


This is what the luminance and color uniformity of the KTC H27T22 look like when measured at 25 different patches across the panel. Please click on the image to see it in high resolution and to examine the data in greater detail. The luminance uniformity is very good, as it deviates less than 10% across the panel. In fact, the highest measured luminance deviation is -8.5% in the bottom left corner of the panel. This is something you have no chance of spotting with the naked eye. Color uniformity could be better. The bottom left and right corners deviate with an average ΔE of up to 4.41, which means the colors lose their accuracy on these parts of the screen in relation to the dead center, which is taken as a reference point. While this isn't an issue when using the monitor for gaming and everyday work, it could pose an issue for high-level color-critical work.

Picture Quality After Calibration

I calibrated the display using the X-Rite i1Display Pro colorimeter and the DisplayCAL software solution. The initial profiling and calibration were done with the luminance target set to 250 cd/m², which presents a happy medium for a comfortable combined daytime and nighttime usage. The calibration was conducted with the adjusted settings which I've listed above.

Here's what we get after calibrating the monitor.



A proper software calibration results in excellent color accuracy, and vastly improved gamma tracking, while keeping the contrast ratio above 1,000:1 – nothing to scoff at for an IPS panel. Of course, we also brought the color temperature closer to 6,500 K. The average color accuracy ΔE went down to 0.39, and the maximum measured ΔE is 1.99, which is good enough even for more demanding tasks, such as photo and video editing. However, you should keep the aforementioned color uniformity issues in mind, as they cannot be fixed even with calibration. Even with such high color sRGB color accuracy, the KTC H27T22 still isn't a great choice for high-level color-critical work. On the other hand, no serious professional will look to gaming monitors for such tasks.

Backlight Uniformity

To give you an idea of the backlight's uniformity, I set the monitor's brightness to 250 cd/m² before taking a photo of the panel in a completely dark room. I did my best to find a combination of the ISO value and shutter speed that would capture the screen in a way that has it look as close to what my eyes were seeing in real life.



There's some backlight bleed around the top and bottom left edge of the panel. Still, it is mostly unnoticeable when using the monitor unless when playing an exceptionally dark game or watching a movie with a lot of shadow content.

Viewing Angles

The viewing angles of the Fast IPS panel built into the KTC H27T22 are excellent. There's no visible shift in colors when you change your sitting position.