YouTube has officially announced that now they support upload and playback of videos with resolution of up to 4K (up 4096×2304 or 2304p and of course also 4096×2160/3840×2160 pixels or 2160p), and although this is not something that every normal user will be able to take advantage of at the current moment, it is still a good move. Actually the update of the supported resolution is more interesting move for people that are working with stereoscopic 3D video than to those that work with higher resolutions than Full HD 1080p (1920×1080). The reason for that being is that commercial cameras that offer recording in 4K 2D resolution like the RED Camera for example are quite expensive for a normal user to afford, but using two consumer grade Full HD cameras you can record stereo 3D video on the cheap and get it in Side by Side format with resolution of 3840×2160. Then you can upload the video in its full resolution and everyone will be able to watch it in its original intended quality in 3D, instead of having to rely on 1080p with half resolution, because of the image being squashed in order to fit into the old supported video format, although this mode will still be available for compatibility reasons with some 3D hardware.
So going to 4K video resolution is indeed a good news for all of us interested in stereo 3D, and in order to get the full quality of normal videos or stereoscopic ones that go beyond 1080p resolution you’ll just have to click on the Original mode when selecting the resolution. This will show the original resolution that the video uses if it is in more than 1080p and up to 2304p, no matter what the resolution is in between these supported modes. Just have in mind that watching 2D or stereo 3D video in 4K resolution online through the flash player requires higher bandwidth, faster CPU and preferably a good video card that can handle GPU acceleration to decode the content in real time. The new 4K support is referenced by the fmt=38 mode in YouTube and that is something that you just might be interested to know if you are interested a bit more into the internal workings of YouTube. What I would recommend to do if you want to actually watch these videos comfortable is to download them on your computer and then watch them, and that is a must if you want to watch stereo 3D videos with 3D Vision anyway.