RED is working on a 6K Dragon sensor. That's insane. Not everyone is using 4K yet, and they're going another 2K higher.

The still comes from filmmaker Tom Lowe (Timescapes), who traveled around Sri Lanka with RED Dragon. He filmed a bunch of elephants for the upcoming IMAX film 'A Thousand and One Nights'. So 6K? He says:
...my main goal was to push the sensor to the absolute of extremes of what it could handle, in terms of dynamic range. The sun is actually in this shot, between those two clouds, and the elephant is completely back-lit. I did not use any bounces or lights of any kind. This is 100% natural light. And remember, elephants have rather dark skin, so all of us on the crew were staring at our monitors, kind of amazed that we were able to hold the sky, and still see the elephant's face and skin. On most cameras, we would have been looking at basically a silhouette. This frame was shot at ISO 1000, 6K resolution (6144x3072), RAW, 85 frames per second.
The sensor shoots at a maximum of 100 fps at 6K. It's so detailed it also captures still at 19 megapixels.

Below is the un-graded frame, converted from RAW and scaled to HD, followed by the final graded frame, courtesy of colorist Ian Vertovec.



And here is a bonus frame, un-graded, shot at 6k, and downscaled to 4k.





Learn more about Tom Lowe's projects at Dreamcore Pictures.