Dell U2719D

Interlace pattern artifacts

On some monitors, particularly but not exclusively those with high refresh rates, interlace patterns can be seen during certain transitions. We refer to these as ‘interlace pattern artifacts’ but some users refer to them as ‘inversion artifacts’ and others as ‘scan lines’. They may appear as an interference pattern or mesh or interlaced lines which break up a given shade into a darker and lighter version of what is intended. They often catch the eye due to their dynamic nature, on models where they manifest themselves in this way. Alternatively, static interlace patterns may 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 dynamic ‘interlace pattern artifacts’. And with the monitor running at its native 60Hz, there were no clear static interlace patterns either. There were some traces of extremely static interlacing if you looked closely, but this would be too minor for most users to notice even from close up. With the monitor overclocked to 74Hz (or much past 60Hz), though, the interlace patterns stood out more. Some shades appeared with fairly faint horizontal bands of a slightly lighter and slightly darker variant of the intended shade. The interlacing at 74Hz wouldn’t be obvious enough for some users to readily notice or be distracted by, however.

Responsiveness

Input lag

We used a small tool called SMTT 2.0 and a sensitive camera to compare the U2719D’s latency with a screen of known latency. To help maximise accuracy, over 30 repeat readings were taken. Using this method, we measured 5.82ms (under ½ a frame at 60Hz) of input lag. This value is influenced by both the element of input lag you ‘feel’ (signal delay) and the element you ‘see’ (pixel responsiveness). It indicates a fairly low signal delay which most users shouldn’t find bothersome.

Perceived blur (pursuit photography)

In our article on the topic, we explore the key factors affecting PC monitor responsiveness. Chief amongst these is the concept of perceived blur, which is contributed to not only by the monitor’s pixel responsiveness, but also the movement of our eyes as we track motion on the screen. This second factor (eye movement) is the predominant contributor to perceived blur on modern monitors, although pixel responsiveness also plays an important role. A method of photography called pursuit photography is also explored. This uses a moving rather than static camera to capture motion on a monitor in a way that simulates both eye movement and pixel responsiveness. This allows both elements of perceived blur to be highlighted, rather than simply capturing pixel responsiveness.

The following images are pursuit photographs taken using the UFO Motion Test for ghosting. The test was set to run at its default speed of 960 pixels per second, which is a good practical speed for taking such photographs and allows both key elements of pursuit blur to be demonstrated. The UFOs move across the screen from left to right at a frame rate matching the refresh rate of the display. All three rows of the test are analysed (dark, medium and light cyan background), allowing analysis of a range of pixel transitions and helping to highlight the effect of different shades (grey levels) on pixel response speeds. The monitor was tested at 60Hz (directly below) and also overclocked to 74Hz. We explore this process shortly. For the 60Hz shots we’ve included a pursuit photograph from a Dell S2417DG as a useful fast TN reference, showing how things look where pixel responsiveness isn’t a significant limiting factor.

At 60Hz (above) the UFO appears soft without sharp focus or clearly defined details. This reflects a moderate amount of perceived blur attributable to eye (camera) movement. There is also some trailing behind the object. Using the ‘Normal’ response time setting, you can see a slight ‘powdery’ trailing behind the object, mostly for the dark background (top row). This indicates some weaknesses in pixel responsiveness. The ‘Fast’ setting gets rid of that but replaces it with much more eye-catching overshoot (inverse ghosting). You can see bright and colourful trailing behind the object. It’s clear from this analysis that ‘Normal’ is the preferred setting to use here. The image below shows how things look with the monitor overclocked to 74Hz.

At 74Hz (above), there are no obvious differences in this test. The powdery trailing using the ‘Normal’ setting extends a little further back, although appears marginally fainter near the UFO body. The UFO itself appears quite similar. The ‘Fast’ setting again appears without obvious overshoot. There is not a distinct difference in perceived blur in this test as the UFO itself appears similar to 60Hz. That is because the extra 14Hz (and 14fps) only has a minor impact in that respect. Observing a broader spread of transitions, including some at faster speeds (i.e. when gaming) and considering how things ‘feel’ rather than just ‘look’ did reveal some slight differences as we explore shortly.

Running a custom resolution (overclocking)

We used a Custom Resolution in Nvidia Control Panel (all timings etc. left at automatic) to set the monitor to 74Hz. This was supported without significant quality degradation or other issues, so we consider this a ‘comfortable’ overclock. The exception to this was the introduction of some relatively faint interlace pattern artifacts that some users could find bothersome, as we mentioned earlier. Setting the monitor to 75Hz or above gave obvious frame skipping on our GTX 1080 Ti, so we settled for 74Hz without pushing things any higher. When it comes to overclocking, mileage may vary and there are no guarantees. The video below shows you how to create a custom resolution for the monitor with a higher refresh rate than the default of 60Hz. Note that AMD has changed the location of their ‘Custom Resolutions’ section since this video was created, but the process itself is similar. Refer to this article from AMD for information on the new interface.

In our experience we consider this sort of increase in refresh rate to be a ‘mild’ overclock that is completely within manufacturer tolerances. There is minimal risk involved and in all likelihood the monitor will last for its useful life in much the same way as if it was run at 60Hz. The general advice we give at this stage as to be aware that overclocking is something which you do at your own risk. We accept no liability should anything happen to the monitor which may or may not be due to running it at an increased refresh rate.

Responsiveness in games and movies

On Battlefield V there was a moderate degree of perceived blur, but this was predominantly caused by eye movement and linked to the 60Hz refresh rate. There were also some slight weaknesses in pixel responsiveness, which caused a bit of additional trailing on top caused by slower than optimal pixel transitions. For some transitions there was a light ‘powdery’ trailing, whilst for some transitions there was somewhat heavier ‘powdery trailing’. High-contrast transitions involving dark and significantly lighter shades would show this, for example. Even this heavy ‘powdery trailing’ was not extreme, though, and only slightly increased overall perceived blur in scenes involving a significant number of such transitions. Sometimes you could observe a bit of ‘break-up’ trailing for these sorts of transitions, too, when some of the shades contained in the object or background colour appeared to leach out slightly. This was not particularly eye-catching and these weaknesses are quite typical on 60Hz IPS-type models. There was a little bit of overshoot in places, too, generally for transitions involving brighter and medium shades. But this was not eye-catching, manifesting itself as trailing that was marginally brighter or darker than the background shades. But only slightly, so quite well-blended in its appearance.

Running the monitor at 74Hz (at 74fps) didn’t substantially affect perceived blur. It gave a slight edge overall, particularly during rapid movement. And some of the ‘powdery’ trailing became a little more extended. What was easier to notice was the edge in ‘connected feel’ this provided. This was not extreme and did not compare to the experience of running a much higher refresh rate than 60Hz. You’re only talking about 14Hz (and 14fps) increase – but it was something we quite liked. We made similar observations on Shadow of the Tomb Raider. This title had a large number of high-contrast transitions as there were plenty of dark areas illuminated by point-sources of light. There was again some ‘powdery’ trailing in places and a little ‘break-up’ trailing, but we didn’t find this distracting or particularly noticeable during normal gameplay. It was by far the more minor contributor to perceived blur compared to the limitations imposed by the refresh rate itself. There was no real overshoot to speak of, just some traces in places but nothing that really stood out. We also enjoyed the bump up to 74Hz in terms of ‘connected feel’, although the slight edge in perceived blur was nothing to write home about really.

We also observed a variety of movie content running at various frame rates, from ~24fps to 60fps. The higher frame rate content appeared much as our game testing, without any real stand-out weaknesses but rather some slight weaknesses for some transitions. Nothing that impeded our viewing pleasure. The lower frame rate content (~24fps and 30fps) appeared much as it would on even a very fast TN model, with the frame rate itself being the key barrier to fluidity. Even the slower pixel transitions on the monitor were fast enough for an optimal performance here without imparting any notable weaknesses. There was again no obvious overshoot, regardless of the frame rate of the content.

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Interpolation and upscaling

On some systems, the 2560 x 1440 (WQHD) resolution might be considered too graphically demanding to use for some tasks. And there are some systems, such as many games consoles, that will only output at a lower maximum resolution such as 1920 x 1080 (Full HD). You may therefore need to run the monitor at a lower resolution, such as Full HD, with the monitor using a scaling (interpolation) process to map the image onto its 2560 x 1440 pixels. To ensure optimal image quality you’ll want to ensure the monitor is handling the scaling process rather than the GPU. So you’ll need to make sure the GPU driver is correctly configured so that the GPU doesn’t take over the scaling process. For AMD GPU users that are using this monitor, the driver is set up correctly by default to allow the monitor to interpolate where possible. Nvidia users should open Nvidia Control Panel and navigate to ‘Display – Adjust desktop size and position’. Ensure that ‘No Scaling’ is selected and ‘Perform scaling on:’ is set to ‘Display’ as shown in the following image.

Note that the monitor includes an ‘Aspect Ratio’ setting in the ‘Display’ section of the OSD, as shown in the video earlier in the review. This includes a ‘1:1’ pixel mapping feature that will only use the pixels called for in the source resolution to present an undistorted, unstretched and unsoftened image with black border around. If you keep things at default and use ‘Wide 16:9’ or alternatively use ‘Auto Resize’, the monitor will use its interpolation process. Running the monitor at 1920 x 1080 (Full HD) provided a somewhat softer look to the image when compared to a native 27” Full HD display. This softening was actually relatively slight, though, with the texture detail and edge definition maintained better than most monitor interpolation processes. You can also adjust the ‘Sharpness’ setting in the OSD if you like a ‘sharper’ look, although we found the neutral setting worked best and higher settings appeared artificially over-sharpened without really improving the image in any way. The interpolation process of the monitor is therefore quite usable should you need to use the Full HD resolution for anything, including console gaming.

As usual, if you’re running the monitor at 2560 x 1440 and viewing 1920 x 1080 content (for example a video over the internet or a Blu-ray, using movie software) then it is the GPU and software that handles the upscaling. That’s got nothing to do with the monitor itself – there is a little bit of softening to the image compared to viewing such content on a native Full HD monitor, but it’s not extreme and shouldn’t bother most users.

Video review

The video below summarises some of the key points raised in this written review and shows the monitor in action. The video review is designed to complement the written piece and is not nearly as comprehensive.

Timestamps:
Features & Aesthetics
Contrast
Colour reproduction
Responsiveness

Conclusion

Dell’s UltraSharp series are an established favourite for users looking for a good mix of image quality and performance. In keeping with its predecessors, the Dell U2719D features a minimalistic design without any bold design features. Matte black and silver plastics, slim bezels and a fully ergonomically flexible stand with reasonably small-footprint base. The accuracy of the factory calibration has been something that has steadily improved with successive UltraSharp generations. This model was no exception, with an excellent factory calibration which would allow most users to be very happy and confident in the screen’s output after simply setting brightness to their taste. For users who prefer a touch of extra vibrancy at the expense of accuracy, the native gamut of the monitor can be used outside of the factory default ‘Standard’ mode. It extends a bit beyond sRGB but not to an extreme degree. Colours appeared rich, in-place and consistent with some good vibrant elements without obvious oversaturation.

The contrast performance was much as we expected given the panel type. A moderate amount of ‘IPS glow’ ate away at some detail peripherally, particularly towards the bottom corners. Static contrast sat close to 1000:1, with a bit of variation depending on settings used. There were no noticeable gamma inconsistencies across or up and down the screen, distancing this model from VA and moreover TN panels where detail levels vary considerably depending on the section of the screen you’re observing. So a reasonable contrast performance, overall. The screen surface departed from other some other recent 25-27” WQHD UltraSharps as it employs a medium (‘relatively light’) matte anti-glare finish. This is not quite as smooth or light and gives a slight ‘misty’ graininess to the image. This was by no means extreme and there was not a smeary or ‘layered’ appearance to the graininess. Overall clarity and vibrancy was maintained well, alongside relatively good glare handling.

As far as 60Hz monitors go the monitor proved quite responsive. There were minor weaknesses in terms of pixel responsiveness in places, giving some ‘powdery trailing’. But this was not really eye-catching and didn’t add hugely to overall perceived blur. There was no noteworthy overshoot and the monitor, overall, made good use of its 60Hz refresh rate. Input lag was also fairly low and, for those who like a bit of an edge in ‘connected feel’ and perceived blur, we were able to overclock the monitor to 74Hz. This introduced some static ‘interlace pattern artifacts’ which some users could find bothersome, although they were reasonably faint and not everyone would find them annoying or necessarily even notice them.

Overall the Dell U2719D is a welcome addition to the UltraSharp series. Some nit-picks would include that we would’ve preferred to see a lighter and smoother matte screen surface employed, there were some uniformity issues on our sample and a 60Hz refresh rate with mild overclockability is somewhat restrictive for fast-paced gaming. But if you’re happy with the refresh rate, then this is a definite contender. It offers strong ‘out of the box’ performance, a range of useful OSD settings and a nice (and sensible) design. So a lot of important boxes ticked. Coupled with a reasonable price tag, we feel this is a model that deserves some careful consideration and perhaps deserves a spot on your desk.


The bottom line; strong ‘out of the box’ performance, decent responsiveness and excellent colour reproduction within the sRGB colour space.

As an Amazon Associate I earn from qualifying purchases made using the below link. Where possible, you’ll be redirected to your nearest store. Further information on supporting our work.