AF point distribution on DSLRs
Does the size of the submirror that directs light to the AF module limit the distribution of AF points to the centre of the frame in DSLRs.
On FF cameras, it appears even with the increasing number of AF points, they 're still bunched up in the middle.
Even Sony SLTs that don't use a submirror also seem to have AF points bunched in the centre.
I for one would find it extremely useful to have greater coverage of AF points on the periphery.
Or are there other problems such as issues with lens eg. field curvature, light fall off, edge sharpness issues?
I'm referring to PDAF of course, and not the on-sensor ones.
Perhaps we'll have to wait for CDAF points that work in conjunction with PDAF or on-sensor PDAF points before we get a wider distribution of AF points?