4K Monitor for Digital Cinema Colour Grading - ColorEdge cG318-4k review

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The ColorEdge CG318-4K appears to be Eizo's play for both its traditional market of particularly exacting stills photographers and for that part of the film and TV business.

Eizo has had an enviable profile among print and design people for a while, famous for displays which achieve more or less everything that the underlying technology possibly can. The CG318 doesn't (can't) have the same contrast ratio as an OLED, but it really does have absolutely everything else. The basic spec list is a worthwhile place to start: with a full 4096 pixels per line, it's a display of about 1.9:1 aspect ratio and capable of displaying not only the most enormous workstation desktops but also a full digital cinema 4K image, not just 3840-wide quad HD as with many monitors described more casually as 4K. Perhaps more importantly, the sheer physical size of the thing, at the best part of 32 diagonal inches, begins to make 4K readily viewable in a way that 24" quad-HD displays only really do if we lean in and squint.

 

Impressive contrast

The thing is, figures near £3000 are mentioned, which is potentially a lot for a monitor when Dell's UltraSharp 32 display, at less than half the price, is also an option. In the end, though, the CG318 starts making Dell look quite expensive, given the yawning gap in feature set. For a start, Eizo mentions a 1500:1 contrast ratio; this is both technologically feasible for a very high quality IPS TFT and readily believable in practice.

Just as a subjective observation, the amount of contrast from the CG318 is literally eye-watering. Selecting the sRGB preset, (much more about sRGB below) and cranking up the variable backlight theoretically puts the monitor way out of calibration, but boy, does it look pretty to the untrained observer. Just as a demonstration of sheer dynamic range, this setup produces a display which doesn't even begin to approach the sheer power of Dolby's HDR displays, but suggest what a practical, affordable home-user version of it might look like. In a darkened room, sunset shots are squintingly bright and blacks remain solid. The backlight only goes up to 300 candela per square metre, which is pretty normal for desktop displays, but the point is that the CG318 serves as a particularly keen example of something that's increasingly well-understood as time goes by: dynamic range isn't really about maximum white brightness, it's at least as much about minimum black brightness.

What's your angle?

While we're discussing contrast, we should talk about viewing angles. Naturally, as a TFT panel, the off-axis performance of the CG318 does vary very slightly. Within that limitation, though, performance is very good. The display enjoys a wide range of viewing angles with consistent colorimetry. Beyond that range, the image just seems to dim slightly, with none of the purplish or whitish glare that becomes obvious on many other IPS TFTs.

Colourspaces

So far, so good; the Eizo CG318 is an exceptionally good full-4K, high contrast TFT monitor, which at £3000 probably wouldn't raise too many eyebrows. What makes the display particularly interesting for film and TV people, however, is that unlike a lot of cheaper options, it has built-in support for not only sRGB and Adobe RGB, but also Rec. 709, Rec. 2020, SMPTE-C and DCI-P3 colourspaces.

The monitor covers 98% of the vast P3 colourspace used for digital cinema work. It is therefore suitable for more or less immediate deployment as a reference display in edit suites and grading facilities, producing anything from Rec. 709 material for current broadcast workflows through to digital cinema mastering.

Other than buying one of the 4K OLEDs, this is something that could be emulated to some extent using a lower-cost TFT designed to display Adobe RGB, plus some sort of colour correction device such as a Fujifilm IS-mini, or an HDLink 4K, should Blackmagic release one. Even so, the total cost of doing this might well begin to approach the value of the CG318 and the results would almost certainly not be as good, given the high performance of the TFT panel and backlight that form the basis of Eizo's display.

Field-ready?

With the ability to upload LUTs using Eizo's supplied software, the CG318 is also more or less ready to go as an on-set monitor, suitably flight-cased and with an SDI converter to suit its HDMI and DisplayPort interfaces (there are two of each, both supporting 10-bit pictures, although the HDMI is a slight disappointment being limited to 30Hz updates). Outdoors on a bright day, the black performance versus OLED might hurt slightly more, although it's hard to see this as a huge problem, given that the CG318 has at least as much contrast as many of the TFTs that are being used for this sort of work at the moment. The lack of an SDI input is a bit of a shame, although the overwhelming majority of Eizo's customers are still photographers and graphic designers for whom the feature would be utterly superfluous.

Calibrating output

Saving the most interesting for last, the thing that makes the CG318 look like a really good deal is the inbuilt calibration. Various people have claimed calibration for their displays in the past – the Dell UP2414Q we looked at came with a calibration sheet – but the ability for a monitor to actually observe its own output is fairly rare. The CG318 includes a mechanical device which swings a sensor boom into position over the display, allowing it to genuinely measure the output from the panel and perform a proper calibration.

Now, we have to reign in our enthusiasm just slightly here: a really good calibration probe is worth more than this entire display and there may be some question over exactly how good the CG318's inbuilt probe can really be for the price. Ultimately, without access to an advanced optical lab, it's difficult to qualitatively assess the situation, so I won't, but at some point, this is likely a better solution than calibrating once at the factory and hoping. Perhaps most significantly, the demo monitor is naturally brand new and the real value of a calibration probe is in ensuring that things remain in trim as they age. Comparison against a really good probe after a few years' hard use might be in order (Eizo warrants ten thousand hours or five years); shall we meet back here in, say, 2019 to discuss?

Conclusion

Overall, the CG318 is spectacular. It is impossible to avoid the comparison with OLED; the CG318 isn't one, but then it's something like two thirds the price of even an HD OLED, and it has inbuilt calibration. There will always be a market – high end film finishing in particular - in which the only fashion dictates that the only acceptable monitoring is either projection or a Sony OLED, but outside that area, in places where purchasing decisions are based on capability not branding, really good 4K monitoring is made a lot more accessible by the existence of this display.