Unlike Z, FUNimation never received film masters for that show. The blue bricks are cleaned up digibeta masters - with mixed success. They're grain-scrubbed, which results in a bit of blurriness, but in some cases it does look better than their two-disc sets from beforehand (if you're not a stickler about the Japanese title cards.)
In fact I think FUNimation had to request film for Z, I'm pretty sure their originalsingles came from tapes too...