For this animation i played with the sapling addon and the eevee render in freestylemode using blender 2.80 beta
I created a tree and a separate foliage object and assigned it a material with an emmission shader to make sure it is evenly lit and creates a uniform color in the final render. Then I animated the camera location and the focal point to create the slider movement and the follow focus event and added a defocus blur in the compositor.
you can download the blend file here
I really like the cinematic feel of this small animation - if I find the time (hahaha) I work on this a little more and turn it into a music videoread more ...