10-16-2016, 08:21 PM
Although Canon lenses have indeed electronic adjustment - all AF lenses in their lens series have this, from a simple to a very complex implementation -, there are quite a few other factors at play as well. With some lenses it is possible to adjust groups or elements individually, electronically, but to solve decentering etc. a lens generally requires taking apart. Also, electronically adjusting may not be all that easy either, amongst others because of the discrete steps in focusing accuracy present.
My perfectly focusing 50L for example took Canon several times to get right, and the last time only because I stayed at the repair centre, explaining exactly to the technician himself how the lens behaved and what I was expecting it to do. It essentially took most of the day to get it right, and I know he did more than just adjust it electronically.
It depends on the lens as well,; another notoriously hard lens to fix from an AF POV is the 85L.
Of course Sigma has the advantage of being a follower in this respect, which allows for 20 years of experience to be built into their lenses and docking stations, and hence making it possible to greatly simplify the operation for their users. it is a great USP for them, while for Canon it likely is the name and the red ring.
Kind regards, Wim
My perfectly focusing 50L for example took Canon several times to get right, and the last time only because I stayed at the repair centre, explaining exactly to the technician himself how the lens behaved and what I was expecting it to do. It essentially took most of the day to get it right, and I know he did more than just adjust it electronically.
It depends on the lens as well,; another notoriously hard lens to fix from an AF POV is the 85L.
Of course Sigma has the advantage of being a follower in this respect, which allows for 20 years of experience to be built into their lenses and docking stations, and hence making it possible to greatly simplify the operation for their users. it is a great USP for them, while for Canon it likely is the name and the red ring.
Kind regards, Wim
Gear: Canon EOS R with 3 primes and 2 zooms, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, tubes; Olympus OM-D 1 Mk II & Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ....