8K is one of our predicted hot topics for this year's NAB and RED is already staking its claim to be an exponent of the art of extreme resolution with the RED Weapon 8K.
Here's some footage taken with this capable camera. It's by filmmaker Phil Holland, who visited Bladesmith Tony Swatton at work in his forge.
What you can see — albeit not in native 8k here on YouTube — is the subtlety and the dynamic range of the format. It makes a good case for the notion that if you shoot in a high resolution, every derivative of your original footage, even at much lower resolutions, will benefit from such extreme detail in the original.
That's because the high resolution original provides extra information to inform any subsequent compressor or down-sampling algorithm. It just looks better however you see it.
Phil has written a Behind The Scenes account of his lighting, post workflow and lenses used in the production here.