The soft AF can be a result from a combination of the contrast reading reported by AF sensor(s) and how smart the AF firmware to drive the lens. Use speedlite to assist the outter AF point(s) before we can blame the issue on any lens.
Apr 13, 2012 at 02:26 PM
Previous versions of mttran's message #10540005 « 5D3 outside AF point issue with wide lenses »
