Picture Quality

The Viotek GFV27DAB features an 8-bit VA panel capable of displaying 16.7 million colors. The screen uses a White-LED (W-LED) backlight unit. It's controlled by direct current (DC), which makes it flicker-free at all brightness levels.

The screen coating on the Viotek GFV27DAB 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 nits, accompanied by a static contrast ratio of 3,000:1, which is fairly standard for VA panels.

To test the picture quality of the Viotek GFV27DAB, I used a combination of the X-Rite i1Display Pro and Datacolor Spyder5ELITE+ colorimeters, and DisplayCAL, a powerful software solution for display calibration and profiling that is completely free assuming you own a supported colorimeter.

Picture Quality at Factory Settings

The picture quality of the Viotek GFV27DAB at its factory defaults was tested right after plugging it in and allowing it to warm up for about an hour. At the factory settings, I've measured a brightness of 260 cd/m², with the color temperature sitting at 8.300 K, which is extremely high. Because of that, the colors were far too cold, and the picture had a clearly visible blue tint, almost like an Instagram filter had been applied. This will of course be one of the first areas we'll focus on when adjusting the monitor's OSD settings. The measured gamma was 2.23, and the static contrast 3,314:1 thanks to a fairly deep black level measuring 0.0786 cd/m².

As I've already mentioned in the introduction, the combination of a 27-inch panel and QHD native resolution (2560x1440) results in excellent picture sharpness, as well as a healthy amount of screen real estate. While you'll have a much better time with an ultrawide monitor for heavy-duty multitasking, the Viotek GFV27DAB will allow you to comfortably work in two windows at once. Many users don't need more multitasking capabilities than that from their monitor.

The first thing you'll want to do after turning the Viotek GFV27DAB on is to venture into its OSD and change a couple of settings. Our main goal is to bring the color temperature down to 6,500 K (or as close to it as possible) while keeping image brightness at around 250 cd/m² without losing gamma accuracy and contrast. Your first stop should be the Color Temperature submenu found in the Color menu, where you have to select User and then manually adjust the gain of the red, green, and blue channels. For my sample of the Viotek GFV27DAB, the best image quality was achieved after leaving the red channel at 50, lowering the green channel to 49, and the blue one to 44. The only other thing left to do was to adjust the Brightness setting to 75 in the Display menu.


The OSD lets you change the gamma on a scale from 1.8 to 2.4 in 0.2 increments, but it's best to leave it at its default value of 2.2. As you can see in the image above, that results in the most accurate measured gamma curve, which closely follows the reference curve. The gamma setting can also be set to "Off," which is bizarre on its own and should be avoided. Once again, just leave the gamma at 2.2 and forget about it.

Let's compare the results before and after adjusting the settings of the monitor. Let me remind you that we still didn't calibrate the monitor; all changes to its picture quality were done through the OSD.


All of the aforementioned OSD changes resulted in a measured picture brightness of 252.19 cd/m² and a measured color temperature of 6.445 K. The bluish tint is gone, and the resulting picture quality is very pleasing to the naked eye. My X-Rite i1Display Pro confirmed that the static contrast ratio actually went even further up, all the way to 3,733:1, with an even deeper black level of 0.0676 cd/m². These are great results for one of the least expensive 27-inch QHD gaming monitors on the market.

What's even more impressive is the measured color accuracy. Without calibration and only a couple of the aforementioned tweaks in the OSD, the average ΔE is as low as 1.03, with only two noticeable deviations; the red color (255,0,0) has a ΔE of 3.09, and the orange color (255,170,0) has a ΔE of 2.35. Of course, when I say "noticeable," these are only noticeable to my colorimeter. The naked eye generally can't spot any color inaccuracies with a value below ΔE 3.


The measured gamut volume of the panel is 102% for the sRGB and 72.2% for the DCI-P3 color space. With our adjusted settings, actual gamut coverage is 98.3% for the sRGB and 72.2% for the DCI-P3 color space.


This is what the luminance and color uniformity of the Viotek GFV27DAB look like when measured at 25 different patches across the panel. Please click on the image to see it in high resolution and examine the data in greater detail. As you can see, backlight uniformity is decent, with the highest measured deviation of -15.23%, present around the bottom edge of the panel. Anything below -15% is next to impossible to spot with the naked eye, so it shouldn't bother you when gaming, surfing, or doing other non-color-critical tasks. When examined across various brightness levels, the brightness uniformity averages -6.55% on the most problematic part of the panel, which is the aforementioned bottom-left corner, passing the nominal tolerance according to the ISO 14861:2015 evaluation criteria. The same is true for the rest of the panel; it either gets a "Nominal tolerance passed" or "Recommended tolerance passed" check in all 25 patches I measured for uniformity. Of course, color and contrast uniformity are taken into account, too. Color uniformity is fine, averaging below ΔE 3 across the panel, and contrast is very stable, with a measured deviation range of 0.73–7.36%, depending on the part of the screen.

With all that in mind, the Viotek GFV27DAB leaves a great overall impression. This monitor can not only be used for smooth gaming, but is also viable for more demanding tasks, including home photo and video editing. For one of the least expensive monitors of its kind, that's quite a feat.

Picture Quality After Calibration

I calibrated the display by using the X-Rite i1Display Pro colorimeter and DisplayCAL software solution. Initial profiling and calibration were done with the luminance target set to 250 nits and by using the sRGB profile.

Here's what we get after calibrating the Viotek GFV27DAB.



After calibrating the Viotek GFV27DAB, the existing minor color accuracy issues were completely gone. The highest measured deviation went from ΔE 3.09 to ΔE 0.95, and the average ΔE dropped to 0.45. These are impressive numbers for a panel of this caliber and pricing.

Backlight Uniformity

To give you an idea of the backlight's uniformity, I set the brightness of the monitor 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.



Any imperfections in backlight uniformity are pretty much impossible to distinguish in real life, even when playing darker games or watching movies and TV shows with a dimmer visual tonality.

Viewing Angles

This being a VA panel, you want to keep yourself in the optimal viewing position for the best visual experience. Even though the color shift isn't apparent when you're adjusting your sitting position, which would be the case with a TN panel, you still want to avoid looking at the monitor at an extreme angle as its picture will look pale. For every normal scenario I can think of, the viewing angles of the Viotek GFV27DAB aren't something you have to worry about.