This lens have no mirror issue with 400D 1.6 crop Canon, but with 5D and 5D Mk II. By removing the rear end lens protecter/shroud, it has no mirror issue up to some 37mm or so, in other words, if it is turn to 35mm focal length position, the mirror issue comes back. To me, lossing just a few degrees in angle of view is no problem. To eliminate the mirror issue entirely, one may opt to further file down the rim of the rear end lens a bit or grind the morror, which I do not consider. The lens can focus to infinity used both Chinese and Novoflex adapters