Out of the box the monitor produced an image that was quite well-balanced overall and richer than many high refresh rate TN models produce (often even after tweaking in the OSD). The gamma tracked at ‘2.3’ on average as shown below. This avoided the ‘washed out’ look imparted by central gamma being far too low, which is a common issue on high refresh rate TN models in particular. The curve bows considerably centrally and the gamma is actually a bit lower than intended at the extreme ends. This is shown in the first gamma graph below, with the monitor set up as per our ‘Optimal OSD Settings’. It shows the bowing nicely although isn’t really high enough resolution to show the lower gamma at the extremes. The second graph shows the results with our ICC profile applied (per our ‘Test Settings’), with tracking much closer to the ‘2.2’ curve.



Gamma 'Optimal OSD Settings' Gamma 'Test Settings' The monitor also includes a ‘Blue Light’ Low Blue Light (LBL) setting. This can be set between ‘50%’ (maximum effect) and ‘80%’ (minimum effect) in increments of 10%. This setting was effective, particularly at the greater effect levels, significantly reducing blue light output from the monitor. Minimising exposure to stimulating blue light in the hours leading towards bed is particularly important to aid a restful night’s sleep. As common for LBL settings, the green channel is left alone so that it remains relatively strong. This minimises the impact on static contrast from applying the setting, but it also imparts a green tint that’s strongest near the top of the screen (due to viewing angle behaviour). The eyes adjust to this to an extent, so it becomes a bit less noticeable in time. We used the strongest LBL setting with further reduction in brightness for our own viewing comfort in the evening. But the LBL settings weren’t applied during testing – beyond that focusing on the LBL settings themselves. We assigned this to the ‘G2 – Racing’ preset and used ‘G1 – Action’ for our ‘Test Settings’, making it easy to activate and deactivate the setting.



Optimal OSD Settings We lowered brightness and made slight tweaks to the colour channels to improve the overall balance of the image. Gamma remained at ‘2.3’ and it wasn’t possible to correct this appropriately to ‘2.2’ in the OSD. The image remained quite rich, although it was lifted up just a bit following the full calibration (with ICC profile) that accompanies our ‘Test Settings’. Assume any setting not mentioned, including contrast, was left at default. We’ve also included the refresh rate set in Windows, just for reference, although this didn’t significantly impact static image quality. Remember that individual units and preferences vary, so these are to be considered a suggestion and won’t be optimal for all users or units.



Brightness= 35 (according to preferences and lighting) Brightness= 35 (according to preferences and lighting) Color Temp.= User Red Color= 50 Green Color= 48 Blue Color= 50 Over Drive= Normal Refresh rate (Windows setting)= 240Hz



Test Settings (ICC profile) We created an ICC profile using our Spyder5ELITE colorimeter to improve gamma tracking and make further refinements to the image beyond what could be done with OSD tweaking alone. The ‘Optimal OSD settings’ above were used as a base, over which our ICC profile was applied. Note that the ICC profile is specific to our unit and, along with the OSD settings, it may not be optimal for all units. You can use the profile in combination with whatever brightness or colour channel adjustments you require. To make use of our profile do the following: 1) Download the ICC profile.



2) Set the monitor up according to the ‘Optimal ‘OSD settings’, although further adjustments can be made if desired. Using a brightness of ‘35’ provided ~175 cd/m² on our unit with the ICC profile applied.



3) This article provides instructions on activating the profile as well as some limitations to be aware of when gaming in particular. Games do generally respond to the profile or at least apply the gamma correction. And even without the profile, the image appears quite rich, so consider the ICC profile a bonus rather than essential.



4) Some web browsers have colour management issues when ICC profiles like this are used. We observed messed up gamma, with gamma being far too low leading to detail that should be blended and masked instead appearing too distinct. This gave an obvious blocky appearance to dark scenes on Netflix content, for example. This is easy to correct on Google Chrome. You simply type the following into the address bar: chrome://flags/#force-color-profile and change from ‘Default’ to ‘sRGB’ then restart your browser. You only have to do this once (set and forget), although what the setting is called may differ depending on the version of Chrome you’re using.





An X-Rite i1Display Pro was used to measure the luminance of black and white using a range of settings. From these values, static contrast ratios were calculated. The following table shows this data, with blue highlights indicating the results under our ‘Optimal OSD Settings’ and ‘Test Settings’ (ICC profile applied). Black highlights indicate the highest white luminance, lowest black luminance and highest contrast ratio recorded (ULMB disabled). Assume that any setting not mentioned was left at default, with the exceptions already noted in the calibration section. Note that changing refresh rate did not impact contrast (where ULMB was disabled).

The average contrast ratio with only brightness adjusted was 849:1, a bit shy of the specified 1000:1 but still decent for the panel type. The contrast dropped a bit under our ‘Test Settings’ to a still reasonable 765:1 and to 700:1 – 776:1 with ULMB active. Note that the default contrast is dropped to ‘45’ under ULMB as this improves shade distinctions for closely matching bright shades with this mode active. Contrast of ~800:1 was maintained with even the strongest ‘Blue Light’ LBL setting active. The highest luminance recorded on this table was 393 cd/m², whilst the lowest white luminance recorded (ULMB disabled) was 68 cd/m². That minimum is a bit higher than some sensitive users might like but will be dimmer than most users would use in general. This gave a luminance adjustment range of 325 cd/m².

The monitor includes a Dynamic Contrast setting called ‘Adaptive Contrast’. This allows the backlight brightness to adjust according to the level of ‘light’ or ‘dark’ on the screen. As usual, the backlight is controlled as a single unit (i.e. there is no local dimming support) so it just works on averages across the entire screen. The gamma is also modified with this setting active, increasing somewhat for darker content to try to increase the ‘cinematic look’. You can set the brightness manually and this is used as a base around which the backlight brightness will adjust. This setting didn’t really seem very dynamic and was rather gentle in its adjustments, good in some ways but not really doing anything dramatic to change the experience. At any rate, we prefer manual control of the backlight brightness over Dynamic Contrast settings like this.





PWM (Pulse Width Modulation)

The XN253QX does not use PWM (Pulse Width Modulation) to regulate backlight brightness at any level. Instead, it employs DC (Direct Current) regulation of the backlight. The backlight is therefore considered ‘flicker-free’, which will come as welcome news to those sensitive to flickering or worried about side-effects from PWM usage. The exception to the flicker-free status is where ULMB is active; this by its very nature flickers at a frequency matching the refresh rate selected.





Luminance uniformity

Whilst observing a black screen in a dark room, using our ‘Test Settings’, we noticed a little backlight bleed and clouding towards the bottom of the screen. This is shown in the image below, but be aware that individual units vary when it comes to uniformity issues such as this. A slight silver or golden sheen (depending on angle) was visible from sharper viewing angles. This so-called ‘TN glow’ is highlighted in a viewing angles video later on. It’s very different to ‘IPS glow’ as it isn’t as strong nor is it readily observed from a normal viewing position.





