Howard Slavitt , Jan 26, 2006; 10:29 a.m.
There are several very long threads about this on the Fred Miranda forum, one on the Canon forum and one on the Alternative forum, I think. There seems to be a problem with the 5D manufacturing tolerances so that shims are often required to get accurate focus. Based on my various experiments -- EE-S screen and using the Canon 1.25 and 2.5 magnifier -- I've concluded that manual focus, at least for me, will never be as accurate as center point autofocus and recomposing. Even for the Canon manual focus lenses (i.e. the TSE lenses), I plan on using the focus confirmation as much as possible. It means you can't use other manufacturers' lenses, but whatever advantage they may offer is likely more than offset by the manual focus errors, unless you happen to have an uncanny knack for manual focusing. Autofocus isn't perfect, but at least for me (and based on what I've read -- see a recent thread on the luminous landscape forum comparing 4 x 5 to an autofocus Hasselblad with digital bank) it's much more consisten and accurate than manual focus.