4k monitor export playback viewing is jittery

[Angelica Amora]

It's about the animations like scaling, fades, zoom. Etc. It's jittery and not smooth especially when exported.

We recently invested in a 4k monitor since we edit in 4k footages and we were so confused as to why the videos looks smooth/almost smooth in the 1920x1080 screen monitor... I don't know if it's from the sharpness of the 4k monitor and the high bitrate of the footage to see those individual pixel. If that's the case then how do the - for lack of better example - Hollywood movies get the highest quality and smooth when shown to 4k tv's or theaters? 

I don't know what more information to tell than the export settings are:

H.264 / QuickTime

Adaptive - High Bitrate / ProRes 422 LT

1VBR pass 

Traget Bitrate: 30

30fps timeline (because I was adviced in this forum to go higher than 24fps if I get a mixed of 23.976, 24, 25, 30, 60fps footages from different cameras so I won't get any frame drops)