Why are folks so keyed up about 4K? At first glance, that's the type of question that answers itself: by definition, a 4096-pixel wide image delivers around four times the resolution of 1920 x 1080, and that's a healthy multiple. It's actually of a broadly similar magnitude to the difference between 1080p and old-fashioned analog NTSC video, and nobody these days questions the value of that upgrade. On the other hand, there must come a point where pixels cease to be visible in a home theater environment, such that buying more of them at inflated prices stops being worth it. Sure, 4K can be a big help with 3D footage, because it boosts the resolution to each eye -- something we experienced with the REDray projector. But what about regular 2D material, which is still very much the default viewing option? That question's been nagging at us, so when Sony invited us back for a second look at its 4K projector, the VPL-VW1000ES, this time with full-throttle native 4K source material rather than just upscaled 1080p, we turned up with a tape measure. Read on for what came next.
The viewing took place in a plush private basement theater at Sony Pictures Europe. It's more like a commercial cinema than a home theater, but on this occasion the VPL-VW1000ES was positioned just six meters (20 feet) away from the screen, which ought to be achievable in an everyday type of mansion. The resulting screen was 3.8 meters (12 feet) wide and 2.2 meters (seven feet) high, which is also feasible in a big home set-up.
After being duly impressed by some native 4K animation clips, we shifted to still images in order to focus solely on resolution. We started out by taking photos of a still projected image of some foliage, from a distance of around two feet from the screen -- by which time the light from the projector had had quite a journey. Unfortunately, Sony's screen was of the acoustic type, which allows sound through from the cinema's speakers behind, and which means our close-up images are riven with tiny holes. Don't let those perforations distract you, however, because the differences in resolution are still clearly visible -- and in fact the holes helped to keep the photos in focus. (The arrow and rectangle in the image above highlight the zoomed-in comparison area, and more specifically the best focus in our samples images was on the base of the tree bud in the lower left corner.)
First, here's the projector playing the image from a PlayStation 3 set to output at a meager 1280 x 720. At this setting, the pixelation was pretty clear and the image was downright fuzzy even when viewed from a distance. By the way of context, each pixel wasn't quite as big as a microSD card, but nearly.
Next, the PlayStation was switched back to its usual maximum resolution: 1080p. This was an enormous difference, with pixels shrinking to around 4mm2. You could easily see the difference between 1080p and 720p when sitting six meters away from the screen: switching from one to the other was a bit like taking a foggy pane of glass off the image.
Then the Sony rep flicked the projector into 4K upscaling mode, which takes the 1920 x 1080 signal from the PS3 and converts it to 4096 x 2160. It does this using Sony's 'Reality Creation' algorithm, which is ironically named but which still does an excellent job of increasing sharpness without creating artifacts. Here, the pixels shrank from 4mm2 to just 1mm2 -- roughly the same size as the tiny acoustic perforations. The increase in detail couldn't quite keep up with that because it was artificially created, but upscaling still managed to deliver that feeling of removing one more foggy pane of glass from in front of the image -- so it's all good.
At this juncture, we had to switch sources in order to get native 4K. This was served up by an ASUS gaming PC containing a Radeon HD 7970 -- AMD's flagship graphics card that can throw a 4K signal out of its HDMI 1.4 port. According to the rep, NVIDIA's GeForce GTX 680 can't quite manage this out of the box. In the close-up shots, the impact of going native is obvious compared to upscaled, and it was also very apparent when sitting three meters away from the screen. When viewing from six meters away, the difference between native and upscaled was there but it was subtle -- it was just a sense of the image being sharper and more natural at the edges of objects. The difference between native 1080p and native 4K at six meters, however, was more marked -- it could only be described as 'subtle' at a distance of nine meters from the screen.
This wasn't a scientific test, because everyone has different visual acuity and the differences we see are ultimately subjective. In addition, the PC image had a slightly different color temperature to the PS3 images, which may have swayed our impressions somewhat. Nevertheless, we have the beginnings of an answer to our original question: if your screen is around three or four meters wide, and if you sit less than six meters away from it, you'll notice a clear benefit in switching from 1080p to 4K for 2D material. Interestingly, you'll also see a significant impact from upscaling your footage through the Sony projector's processing engine -- which makes 'Reality Creation' one of the stars of this show, not least because 4K content is so hard to find.
Beyond that, it's hard to say much without getting philosophical. Does resolution really matter, when a good movie is readily enjoyable on a lowly qHD smartphone? Isn't it more about the quality of the content? But if there was no substance to the quest for greater resolution, then generations of magazine publishers wouldn't have demanded 300dpi, nobody would have worshipped the pixel-free magic of celluloid (aside from its other qualities), and no one would have cared about the Retina Display on the new iPad. 4K is part of one big push to totally eradicate the pixel: to make an image look like a natural and infinite swirl of colors rather than something generated by computer. That's exactly what the VW1000ES delivers and even though it's still a very niche product for niche material, it represents the future.