I don’t think there’s any reason we couldn’t make a store 18k video.
And we could make screen at much higher resolutions that that at imax size, or even quite a bit smaller, though I suspect it would be absurdly expensive.
It is technically possible but you’re right it would be absurdly expensive.
Storing it isn’t the problem, you’ll still need to be able to record and project at that resolution.
As I said I’m sure we could make screens that could do that. They would be absurdly expensive and heavy and stupid, but it could be done. Not worth it though.
And it looks like at least 16k cameras have been made.
The screens aren’t the problem. It’s often the hardware driving it. The current top generation of gaming gpus struggles at 8k. There’s very little chance of being able to render and play 16/18k
Rendering video and rendering games are pretty different. Video is generally easier especially once it’s mixed down.
