I've started playing with PTGUI and stitching together 360 panoramics shot with the P3. But I'm having trouble with filling in the sky. There are so many shades of blue in the sky that I can't seem to get a nice blending into the area above the camera POV. Anyone have a good solution? I need to go back and fix the stitching errors, but that's no problem, I can handle that. It's the sky that's giving me headaches.