The lights pick up the rain

[Maybo]

I’ve watched a video about Disneyland. Its night show with light effects was in rain. I saw a comment. What does “pick up” mean in that comment?

 

[emsr2d2]

The light shining on the raindrops as they fell was pretty/impressive to look at. If lights "pick up" something, it simply means that they shine on them. Those things don't have to be moving.

The light of the moon picked up the craggy edges of the mountain.
The streetlight picked up the hundreds of tiny insects and the bats chasing them.