Alternative alpha channel codec with smaller file sizes?

[roxics]

We've used the Quicktime Animation codec in the past with good results, but for some reason I can't seem to import them into Premiere Pro CC anymore.
So we started using DNxHD with an alpha channel and the file sizes are just too huge. A 20 second 1080p file is 1.9GB and we've got 40 plus files that need rendering.
Is there another codec that supports an alpha channel we can use that has more manageable files sizes?

 

[roxics]

I should note, we are on Windows boxes.

 

[roxics]

Totally forgot about png image sequences. This thread can be deleted. So much smaller. Went from 1.9GB to 16MB per graphic.