> Sony's incredible array of on-plane focus sensors and focus algorithms (Canon's DPAF may actually compete, if turned loose/optimized further) I'm reasonably

> Sony's incredible array of on-plane focus sensors and focus algorithms (Canon's DPAF may actually compete, if turned loose/optimized further) I'm reasonably convinced that DPAF will probably work out better than Sony's approach in the long run – every photosite essentially doubling as a PDAF sensor seems more future proof than scattering 100+ dedicated PDAF sensors over the chip. The problem with the latter is that if Canon can develop the software to really exploit DPAF (there's no reason in principle that you couldn't, say, let users chain together an arbitrary number of pixels into selectable AF points placed wherever they want outside of the extreme edges of the sensor), there's no good response with dedicated PDAF, because the more dedicated sensors you place on the chip, the more pixel gaps you create, and the more demosaicing algorithms are forced to infer pixel colours with missing mosaic values. There comes a point where the visual quality will suffer.