iMac 4K screen resolutions

[Spectrum]

Hello, I've done plenty of searching, but nowhere can I find a list of the scaled resolution that are available for the iMac 4K. Anybody?

I'll be coming from a 17 inch 1920x1200 MBPro (and 1680x1050 15 inch MBPro), so am interested in the options available and the relative PPI of the icons etc compared to what I am used to.

Second question: Do the OSX animations remain smooth on the iMac 4K when running at greater effective resolutions than base?

 

[Hellhammer]

The new 4K iMac has a display resolution of 4096×2304, which by default can show the same amount of information as a 2048×1152 non-Retina screen. Using OS X's Retina scaling, you can switch into 2304×1296 and 2560×1440 display modes. So if you want, you can use this 21.5-inch iMac to show the same amount of information as a 27-inch iMac, a nice added benefit to using a Retina screen.

http://arstechnica.com/apple/2015/1...ter-screen-21-5-inch-4k-retina-imac-reviewed/

 

[blufrog]

I have the 5K and everything is smooth most of the time.

If I run at "Default for display", then everything is smooth except when it comes to scrolling e-mail or iTunes, though in the case of iTunes my collection is on a network drive.

If I run at higher resolutions, again everything is smooth most of the time, but the above scrolling issues become slightly more noticeable.

The scrolling is mostly smooth, with the occassional tiny stutter. IMHO it is unavoidable.

In terms of PPI, it's a resolution vs. screen size issue. It might work out slightly lower, but still look good. The 5K looks indistinguishable from my 13" rMBP.

 

[broadbean]

What I find weird is 1920 x 1080 is not an option.