Tahiti Update

I posted on Facebook on April 3 that I was starting this puzzle.  Now it's May 16, and I have assembled all of the pieces except the ones that are 100% blue sky, maybe 2/3 of the puzzle complete.  Now comes the hard part.  The bottom part of the sky is much lighter, and I can us color to stratify the pieces to some extent; however, the very top is made of hundreds of quite dark blue pieces, hard to distinguish.  As you can see, I can't even figure out how the border goes together yet.

Still, I'm pretty pleased with my progress.  Just 1,300 or so blue pieces to go.