The term 8K is not yet established very well, but will describe several resolutions with a horizontal resolution of about 8,000 pixels analogous to the 4K resolution. At the moment the only approved standard of an 8K resolution is 7,680 x 4,320 as part of the Ultra HD standard. It is used in digital television and known as 8K UHDTV (4320p).
The resolution of 8K UHDTV results in 33,177,600 pixels, which matches the pixel count of HDTV (1080p) times 16. The aspect ratio stays the same: 1.78:1 or 16:9. Because of this upscaling of 1080p or 2160p material will be very easy.
In the second quarter of 2013 Astro Design announced the camera AH-4800 which is capable of recording 8K footage. Also several TV manufacturers announced 8K devices.