Given the price, some 27% higher than the equivalent Canon EF 500mmL f/4L IS II USM that now shuns UD (ED) glass in favor of Fluorite and includes an optical stabilized system, there’s no doubt the Sony is an expensive choice. Nevertheless, it is a welcomed addition to the range. Even if at first sight it appears that sharpness is not one of its strong points, it’s at an acceptable level for the current Sony full-frame cameras. As for chromatic aberration, distortion and vignetting, these image-degrading properties are handled quite well, but the 4.3Tstop transmission is disappointing. We’ve not yet had the opportunity to test rival offerings for direct comparison, so the alternatives may not actually perform any better, or be any more suited to higher resolution sensors. At around $4,999, Sigma makes a 500mm f/4.5 EX DG – it lacks, however, the fast-focusing HSM option that is present in the Sony mount. Alternatively, the recently upgraded $7,500 Sony 300mm f/2.8 G SSM II may be an option with teleconverters; Sony users are however somewhat limited in choice, as the 500mm f4G SSM is the only super-telephoto currently available to them.