I like these specific roundups, very useful for owners of the cameras involved. But I'm a little confused by how the overall scores are tallied. The Canon 100mm F2 EF rates above the Zeiss 100mm F2 ZE by one point, but a closer look at the scores for individual areas shows the Zeiss to equal (transmission, vignetting) or better (sharpness, chromatic aberration, distortion) the Canon in all areas. How then does it rate as one point worse overall? Is it because it doesn't auto-focus on the 6D? How many points are awarded for AF.