BenQ EW2770QZ

Interlace pattern artifacts

On some monitors faint interlace patterns can be seen during certain transitions, particularly noticeable where light shades (muzzle flashes, explosions etc.) briefly pop up on the screen. These are sometimes referred to as ‘inversions artifacts’. Alternatively, static interlace patterns can be seen with some shades appearing as faint horizontal bands of a slightly lighter and slightly darker version of the intended shade. We did not observe any such artifacts on this monitor.

Responsiveness

Input lag

A utility called SMTT 2.0 was used alongside a sensitive camera to compare the latency of the EW2770QZ with various monitors of known input lag. We took over 30 repeat readings to maximise accuracy. Using this method, we measured 3.85ms (under 1/4 of a frame) of input lag. This value is influenced both by the element of input lag that you see (pixel responsiveness) and that which you feel (signal delay). It indicates a very low signal delay that even sensitive users shouldn’t find problematic.

Perceived blur (pursuit photography)

In our responsiveness article we explore the factors which influence monitor responsiveness. One of the key concepts explored is ‘perceived blur’, which is contributed by both the pixel responses of the monitor but also the movement of our eyes motion is followed on the screen. It’s actually this second factor that predominates on modern monitors. We also explore a technique called ‘pursuit photography’, which uses a moving rather than stationary camera to capture motion in a way that reflects both pixel responsiveness and eye (camera) movement.

The images below are pursuit photographs taken using the UFO Motion Test for ghosting, with the test running at the default speed of 960 pixels per second. This is a practical speed for such photography and a good speed to highlight the key elements of perceived blur. The UFO moves across the screen from left to right at a frame rate matching the refresh rate of the display. All background shade levels (dark, medium and light) were used and all three ‘AMA’ (‘Advanced Motion Acceleration’) settings on the monitor were tested. The final image shows a 60Hz reference monitor, namely a Dell S2417DG. This monitor offers rapid pixel responses without significant weaknesses, providing a good idea of what to expect in this test where pixel responses aren’t really a limiting factor.

You can see that, in all cases, the UFO body appears quite soft and unfocused. This reflects a moderate degree of perceived blur related to eye movement and linked to the 60Hz refresh rate of the display. Varying degrees of trailing behind (i.e. to the left of) the UFO can be seen as well, which is down to weaknesses in pixel responsiveness. With ‘AMA’ set to ‘Off’, you can see a fair amount of trailing behind the UFO for all backgrounds tested here. Setting this to ‘High’ offers a significant improvement, cutting down the trailing nicely. There is still a small amount of ‘powdery’ trail behind the object. This is most pronounced but still fairly faint for the dark background and to an extent the medium background – the lighter background, meanwhile, doesn’t have noticeable trailing behind it. The ‘Premium’ setting replaces this trailing with more noticeable inverse ghosting (overshoot). This is caused by excessive grey to grey acceleration, giving an obvious bright trailing behind the object for all backgrounds. From this assessment, it’s clear that ‘High’ is the optimal setting to use. Note that we will not be including a section on ‘overclocking’ in this review as the monitor skipped frames when set above 60Hz.

Responsiveness in games and movies

On Battlefield 1 (BF1) there was a fair amount of perceived blur, caused mainly attributable to eye movement and therefore largely as you’d see on even the fastest 60Hz LCDs. For the most part pixel responses were rapid enough to deliver an experience free of noticeable trailing beyond that. There was a little bit of additional trailing in places, though, which increased perceived blur by giving an additional ‘powdery trail’ behind some objects. This was most pronounced (but still not particularly bothersome) for transitions involving fairly bright shades. Moving past a rock or tree trunk with bright clouds behind, for example, produced a little bit of trailing that added to perceived blur. There was no obvious overshoot, either, although there was a small amount here and there. It generally manifested itself as a sort of ‘snail slime’ trail of a slightly more transparent variant of the shades involved in the transition. This blended in quite readily and certainly didn’t jump out at us as bright or ‘shadowy’ overshoot might.

We made similar observations on Dirt Rally, where it was eye movement that was the predominant cause of perceived blur on the monitor. There were again some weaknesses beyond this, but nothing major. When racing at night some of the more ‘troublesome’ transitions were introduced, where you could see a bit of extra trailing behind bright lights set against a darker background. This was still the more minor component of perceived blur and if users found this bothersome they would undoubtedly find any 60Hz LCD too limiting. There was no obvious overshoot, again just a trace here and there that we had to specifically look out for to really notice. These slight weaknesses in pixel responsiveness were too slight to come into play when watching our Blu-ray test titles. These are limited in their fluidity by the ~24fps frame rate at which they run, and they were presented much as they are on the fastest 60Hz LCDs in terms of motion performance.

Interpolation and upscaling

Not everyone has the GPU power capable to run all of their games or applications at 2560 x 1440 (WQHD), or they may be using a games console or other device that is limited to a lower resolution. Such users may want to run the monitor at 1920 x 1080 (Full HD or ‘1080p’) instead. The monitor performs an interpolation process when it is set to run at a non-native resolution such as this. To ensure the monitor is handling this, rather than inferior GPU scaling being used, you’ll need to make a quick trip to the graphics driver to make sure everything is set up appropriately. For AMD GPU users this is automatically handled by the monitor when gaming, by default. Nvidia users should open the Nvidia Control Panel and navigate to ‘Display – Adjust desktop size and position’. They should ensure that ‘No Scaling’ is selected and ‘Perform scaling on:’ is set to ‘Display’ as shown below.

The interpolation process provided a somewhat softer look to the image when compared to a native Full HD model of similar size. However; the image retained superior sharpness and detail levels to many monitor interpolation processes we’ve seen. The monitor is certainly usable at 1920 x 1080 without the image looking completely odd or as if everything has been placed under some extreme soft-focus filter. There are imperfections, as with any interpolation process of this type, but these are less pronounced than on quite a few models we’ve tested. If you’re sitting back a bit and using the monitor for console gaming at Full HD, for example, you’re not likely to find these imperfections too bothersome. You also gain a bit of flexibility in terms of sharpness control on the monitor, although we found the default level of ‘5’ optimal. Adjusting this simply made the image look odd rather than making it look more detailed or closer to a native Full HD image. There is also a ‘Super Resolution’ feature than can be set to 3 different intensity levels. Even at a level of ‘1’, the lowest with the feature enabled, things simply looked odd and as if a weird Photoshop filter was applied.

As usual, if you keep the monitor at 2560 x 1440 and are viewing lower resolution content (such as a movie), then it is the GPU or movie software that handles the scaling rather than the monitor. This gives a slight softening when compared to running the content on a native Full HD display, although this is not something most users should find bothersome.

Conclusion

For those looking for strong all-round performance and a pleasing but not extreme pixel density, 27” WQHD (2560 x 1440) models remain popular choices. The BenQ EW2770QZ offers this resolution and combines it with a 60Hz AHVA (IPS-type) panel. The monitor itself has a sleek homely design, but has a stand that is limited to tilt as the only ergonomic flexibility. This is quite different to the solid fully-adjustable stands offered on some BenQ models, for example their ‘PD’ and ‘BL’ series. The screen does at least include 100 x 100mm VESA holes for alternative mounting, if the stand ergonomics are an issue. One of the key new features of the monitor is B.I. + (Brightness Intelligence Plus). We found this worked in as much as the monitor reacted to changes in ambient lighting and content on the screen. The adjustments made didn’t really tally with what we’d consider optimal in most cases, though, and we didn’t find the setting of any practical benefit. The hardware itself (light sensor) certainly works and is nothing new to BenQ monitors, but they’ve yet to make proper use out of it by offering the sort of flexibility it needs in the real world. Namely, the ability to set upper and lower limits for brightness – couple that with a clock on the monitor that allows colour temperature to adjust according to time of day and you’d have a very tidy solution.

The contrast was largely as we were expecting given the panel type and specifications, with just under ~1000:1 static contrast measured (a bit of variability depending on settings) and the usual ‘AHVA glow’ eating away at some peripheral detail. We don’t usually like to talk too extensively about uniformity, as it varies between individual units of the same model, but we were quite impressed by the luminance uniformity of our unit when displaying white. Less so with black (there was quite a bit of backlight bleed), but you can’t win all the battles. The monitor provided rich, varied and accurately represented colours straight from the box with generous sRGB coverage and an effective sRGB emulation mode that cut back on the gamut a little. Reducing brightness is all some users would feel the need to do – the flexibility is also there to adjust gamma and colour channels in the OSD, according to uses and preferences. As usual we found BenQ’s Low Blue Light (LBL) settings to be well implemented and easy to activate, too. We were also pleased with the choice of screen surface (very light matte anti-glare), as this provided a relatively clean and ungrainy look to the image. You could have the best calibrated monitor in the world with superb colour reproduction and amazing contrast, but if the screen surface provides a smeary or grainy look to the image it simply mars the result.

In terms of responsiveness, it’s clear from the 60Hz refresh rate that this was never intended to appease hardcore gamers. Nonetheless, it ticked a lot of boxes for those who are happy with the limitations of the 60Hz refresh rate. There was very little input lag, which is far from a given on 60Hz WQHD monitors. The pixel responsiveness was also quite well tuned, with most of the perceived blur being attributable to eye movement rather than pixel responsiveness. There was no obvious overshoot and only minor additional trailing in places. Overall, then, it’s fair to see this model ticks a lot of boxes when it comes to ‘core performance’. It’s a capable all-rounder, but it doesn’t offer the ergonomic flexibility or solid stand build quality of some competing products. It would also be disappointing for those expecting great things from the B.I. + feature. And we still feel there is so much wasted potential with what is clearly a sensitive and capable light sensor integrated fairly neatly into the monitor. A bit of flexibility on the software side (OSD) would go a long way to making this sensor more useful in the real world.

The bottom line; strong core performance and decent aesthetics on one hand, limited ergonomic flexibility and a fairly uninspiring ‘headline feature’ (B.I. +) on the other.

 

Donations are also greatly appreciated.