I took four shots using a Sigma 8mm fisheye lens connected to a Canon EOS 7D body. The angle of the camera was around +30 degrees, which gave me a hole at the nadir but I didn’t need to work on the zenith because PTGui Pro took care of that for me. I then processed the equirectangular image in CubicConverter. I converted the file to a Cubic QuickTime Movie and then exported the bottom face to Photoshop where I fixed the Nadir. Back in CubicConverter I replaced the fixed bottom face and converted the resulting QuickTime Movie to a equirectangular image.