davidcole:macuser: First off, I think you're confused by horizontal/vertical width. 4096 is the horizontal width of a frame, 2160 is the vertical height.
There is also a 2k standard which refers to a frame that is 2048px wide, that is cropped down in post production to create a 1920px wide frame (1080P).
If someone was trying to say that 4K meant 2160, they're wrong, or probably referring to the vertical height of frame.
The 4k standard will revolve around two widths, 4096 and 3840 px wide. Sony is selling TV's now that are 3840x2160.
But yea - pretty confusing how they changed from vertical to horizontal in their branding...probably because all the pro film camera's call it 4k, not 2160p.
No I'm saying it shouldn't be called 4k at all. We should either stick with names, ie HD (720p) Full HD (1920x1080) Ultra HD 3840x2160 and Whatever they will call next next one, super maxi HD?!?! 7680x4320 (this correct? I multiplied 1080 x 4)
And yes I know that broadcast/production use 2, 4 and 8k for the widths as they have never standardised on a vertical resolution. But I think production has been, and probably should be divorced from the consumer market in terms of naming.
Didn't you just fall foul of your same argument (720p vs 1920x1080?) :)
I personally think 1k, 2k, 4k etc.. is all just easier for the average punter to understand. The HD/Full HD, Ultra HD, Uber HD... Sounds silly and specifying the resolution just takes up space... but that's just me.

