Picture Quality

The EIZO FlexScan EV4340X features a 42.5-inch IPS panel with a 4K (3840x2160) native resolution. This gives it a dot pitch of 0.245 mm and a pixel density of 103.67, resulting in good image sharpness – significantly better than what you'd get from a regular 24-inch Full HD monitor, but a tad worse compared to a 27-inch 1440p monitor.

By default, Windows 11 recommends using 300% scaling on the FlexScan EV4340X, which results in comically huge UI elements. It appears Windows assumes you'll be looking at the screen of this size from far away, which is the only situation when 300% scaling can make sense. From a normal sitting distance, the screen is so large that you can easily get away with 100% scaling (in other words, no scaling is applied). The icons and UI elements will still be large enough to remain perfectly readable, and you'll get a truly massive amount of screen real state to work with, which is aligned with the entire existence of this monitor. Four windows can be opened at once, one in each "corner" of the screen, and used with absolute ease and comfort. Depending on the type of content you want to display in a window, you can get away with eight or more windows opened simultaneously. Even if you're not connecting it to multiple sources and utilizing the integrated KVM switch, the FlexScan EV4340X is still a multitasking monster.

The panel is illuminated by a capable LED backlight system. The backlight unit is controlled by direct current (DC), which makes it flicker-free at any given brightness level.

The screen coating on the EIZO FlexScan EV4340X 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 350 cd/m², accompanied by a static contrast ratio of 1,000:1.

To test the picture quality of the EIZO FlexScan EV4340X, I used a combination of the X-Rite i1Display Pro, DisplayCAL – a powerful software solution for display calibration and profiling that is completely free if you own a supported colorimeter – and Calman, the industry-standard display testing and calibration software suite.

Picture Quality at Factory Settings

I tested the picture quality of the EIZO FlexScan EV4340X at its factory defaults right after plugging the monitor in and allowing the panel to warm up for about an hour.


At default settings, the EIZO FlexScan EV4340X performs solidly for a monitor primarily focused on sheer screen size rather than ultimate color performance. EIZO's monitors are always well-tuned straight out of the box, and the FlexScan EV4340X is no exception. This is particularly visible when examining the RGB balance and white color temperature, which almost perfectly matches the 6,500 K target, measuring 6,505 K. That directly translates into excellent grayscale accuracy (average ∆E is 1.3). The color accuracy measurements show that the monitor is tuned for the sRGB color space, with only a slight overshoot in the reds and blues. The average color accuracy is very good (∆E 1.34), and the maximum ∆E does not exceed 4, with pure red being the biggest offender—simply because it reaches a bit outside of the measured sRGB color space. With a static contrast ratio of 877:1 and colors almost entirely clamped to the sRGB color space, the EIZO FlexScan EV4340X may not impress with vividness and punchiness, especially if your other monitor(s) have wide gamut panels. However, as far as sRGB performance goes, there is little to complain about. I would like the gamma curve to look a bit better, especially in the 0-40 level range, where the gamma is consistently lower than it should be. Some crushed shadows are to be expected, but with media consumption being a very low priority for this monitor, I do not see this as a significant issue. In terms of color gamut, the monitor covers 95% of the sRGB spectrum, with an sRGB gamut volume of 97.6%. It also achieves 68.9% DCI-P3 coverage (69.1% volume) and 66.1% Adobe RGB coverage (67.3% volume), further cementing its focus on the sRGB color space.

This is one of the rare cases where I wasn't able to make significant (if any) improvements to the out-of-the-box picture quality by playing with the OSD settings. While it's possible to further improve the RGB balance and increase the average grayscale accuracy to ∆E 0.7 by altering the individual color channel gains in the Color > Advanced Settings > Gain menu (on my sample of the FlexScan EV4340X the best results were achieved with the red channel set to 83, green to 100, and blue to 90), doing so actually decreased the overall color accuracy and introduced no improvements to gamma. In the end you're best off just leaving the monitor at factory defaults, which comes as great news to many users, especially those that plan to use the monitor in a business environment and for mass deployment. If you're after a consistent brightness level, simply turn the Auto EcoView and EcoView Optimizer 2 features off. Of course, if you want to keep the power consumption as low as possible, leave both on.


This is what the luminance and color uniformity of the EIZO FlexScan EV4340X look like when measured at 25 different points across the panel. Click on the image to view it in high resolution and examine the data in greater detail. The luminance uniformity is excellent across the panel, which is quite a feat for an edge-lit screen of this size. The color uniformity is generally acceptable, but the contrast deviation isn't ideal, as it surpasses the 10% mark across the upper edge of the panel. Luckily, this isn't something you'll ever notice when using the monitor for most productivity tasks.

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.



The photo shows some backlight bleed in bottom corners of the panel. I didn't find it distracting or was even able to spot it while using the monitor. The upper corners seemingly also show backlight bleed, but that's actually IPS glow, which, unlike backlight bleed, disappears when we move further away from the panel or readjust our sitting position. If the panel was smaller, my camera could capture it without any visible IPS glow.

Viewing Angles

The viewing angles of the IPS panel built into the EIZO FlexScan EV4340X are very good, but some vignetting is present when the panel of this size is observed from a normal sitting distance. I didn't find it distracting in everyday usage. A curved panel could theoretically be used to fight vignetting, but nobody makes curved 43-inch 4K monitors, so if that's the combination of screen diagonal and resolution you're after, you're stuck with flat panels, like the one on the FlexScan EV4340X.