With that in mind, we tested the effect on a shot that involves the first doomed flea hanging down a perilous crevice.
Here is an original frame from the shot, animated by Keenan.

Then, the director submitted a staggering masterpiece of a concept sketch to Phil, our matte painter...

Phil then expanded on the existing set, adding depth and light effects,

And here is the final shot with the flea reintroduced and a temporary sky in place. Note, this is NOT a final shot, as the sky needs changing, focal effects need to be added, and the snow is missing - but you get the idea!

Cool, eh?