Apple's latest 27-inch iMac's display delivers eye-watering 5K resolution, which seems a little odd considering there's barely any content, if any, that's recorded in 5K.
A little history: The next leap in screen resolution is called ultra HD, or 4K. It's about twice as sharp as the regular HD you're probably used to now.
Last year, Apple introduced a new iMac that upped the ante. The screen has a 5K resolution, which means it has more pixels than necessary for even the highest quality video shot today.
Last week, Apple raised the resolution on the smaller, 21.5-inch iMac, giving it the standard 4K display.
So, why does the larger iMac need a higher resolution? Surely 4K is enough, right?
5K is mostly for video or photo editors who like to edit 4K video in full resolution.
With a 5K screen, video editors can have the 4K video they're editing open in full resolution within video editing software while leaving enough pixels for additional editing tools around the video.
This graphic demonstrates that pretty well. Imagine you're a video editor using a program like Final Cut or iMovie. The 27-inch iMac lets you view a preview of the video in full 4K resolution:
The video is still 4K, but there's just an extra K of pixels for the editing tools.
A video editor using the 21.5-inch 4K iMac wouldn't be able to edit a 4K video at full-resolution because the 4K video would take up the entire screen (at full size), and they wouldn't have ready access to the software's editing tools.
More pixels also means more detail for photo editors.
Apart from that, there's little benefit of having an extra "K" of resolution, as any 4K content you might have won't look noticeably better on the 27-inch iMac's 5K screen.
