On Apr 1, 2012 4:52 AM, "Richard Knoppow" <dickburk@xxxxxxxxxxxxx> wrote: > >> If the focus shifts when one stops down then that will hopefully be catered >> for by the increased Depth of Focus. >> > > It depends on the lens, sometimes its more than depth of focus will compensate. You can't ignore it. > Some lenses, mostly the Planar-derived types on good 35mm cameras seem to be nearly free of it. Thanks Richard. Perhaps I'll check that out on my lenses some rainy day.