Making the Toshiba 55ZL2's lack of current and, seemingly, future Quad HD source compatibility all the more tragic is that when it's fed a 4k image, its pictures are simply staggering. Fears that you might only appreciate the impact of so many extra pixels of picture information on projection-sized screens are instantly put to bed, as the 55ZL2's 55in screen proves amply large enough - even from an entirely standard viewing distance - of underlining just why we feel that 4k rather than 3D represents the long-term future of TV.
Quad HD changes everything
The Quad HD demo reel, which contained a variety of real video footage ranging from street scenes to woods and inviting-looking pools, looks nothing short of revolutionary, and incredibly tangible, for want of a better word. Basically the extra detail in the picture makes you forget you're watching a TV and transports you almost viscerally to the place you're watching.
You don't have to be an experienced TV reviewer or even AV enthusiast to see the difference, either; we invited in a procession of perfectly ordinary and in some cases tech-cynical men and women to see the Toshiba 55ZL2 in all its 4K glory, and not a single one failed to be gobsmacked by what they were witnessing. Honestly, it's an experience that really does have to be seen to be believed, and instantly allows the 55ZL2 to claim the finest picture quality ever seen on any TV.
Of course, though, with fancy dedicated 4K servers and non-standard digital interfaces not readily available to the world at large, for most people the 55ZL2's 4K talents will be restricted to its ability to upscale standard and normal high definition sources to its quad HD native pixel count. So it's just as well that with HD sources, at least, the upscaling system works quite well.
Full HD into Quad HD will go
Activating Toshiba's Resolution upscaling engine - driven by the set's built-in, proprietary and uber-powerful Cevo Engine processors - HD pictures receive noticeable extra detailing and crispness, without noise levels being aggressively increased. It must be said that upscaled full HD pictures aren’t nearly as pure and just plain beautiful as native 4K ones, but any improvement on the full HD images found on lower-resolution TVs has to count as a significant justification for at least a chunk of the 55ZL2’s price.
The upscaling engine fails to bridge the gap particularly well between standard definition and the panel’s 4k resolution, though, as even the Cevo Engine can’t calculate the vast amounts of extra pixels of image data it needs to without leaving the image looking somewhat noisy and soft.
Shifting our gaze to the Toshiba 55ZL2’s other innovation, the glasses-free 3D, it must be said right away that Toshiba has improved the technology hugely since we first saw it in action. The painfully obvious vertical ‘seams’ in the picture have gone, and 3D Blu-rays look much more detailed, less soft and just more "HD" than they did before. The sense of depth in the image has been increased, too, without sacrificing foreground sharpness, and the fact that you’re not wearing glasses means that 3D images enjoy just as much colour dynamism and extreme brightness as the screen delivers in 2D mode.
That you don’t have glasses on also makes the experience seem much less artificial and vastly less fatiguing on your eyes. Toshiba has even managed to cater for as many as nine different seating positions for the 3D effect, with a built-in camera on hand to track where each viewer is and automatically calculate the 3D picture output accordingly.