Sigma Corporation would like to announce a firmware update for the SIGMA 100-400mm F5-6. 3 DG OS HSM | Contemporary for Canon and SIGMA MOUNT CONVERTER MC-11 EF-E is now available. By updating the firmware, the lens will offer improved AF performance.
Also, the latest firmware of the SIGMA MOUNT CONVERTER MC-11 EF-E will not only Read more. . . . canonrumors.com