This is a gif of me doing a pushup.

This is a link to a higher resolution (but black and white) version of the gif, in case if you want a closer inspection or if embedding this gif doesn't work.
So my question is, am I losing the protraction of the shoulderblades way too early? Especially on the way up it looks like I stay retracted for the entire first half of the movement.
Correct me if I'm wrong, but shouldn't I start protracted and smoothly go into full retraction as I near the floor, instead of retracting so early on the way down and protracting so late on the way up? Or am I just over-thinking things
And if so, what can I do to correct this? Just strengthen the serratus, or is there some cue I can use to smooth out my scapular rhythm?
Thanks guys!