Panasonic is getting a lot of criticism for it’s DFD autofocus system. While it works pretty well in stills mode it’s still sometimes frustrating to use in video. But Dpreview seems to be pretty optimistic about the DFD future:

The updates in the S5 show us a couple of things. Firstly, that Panasonic is well aware of the criticisms being leveled at its cameras and is continuing to fine-tune its software to squeeze everything it can out of the current hardware.

But, more significantly, the improvements we’re seeing when shooting stills and when using AF-C during bursts of stills in particular suggest that some of the downsides we’ve seen in the past aren’t necessarily inherent flaws of the DFD concept. Instead they’re aspects that can improve as sensor readout and processing power improve. You don’t need to be a semiconductor physicist to recognize that improvements in those areas are always coming.

In principle, in the long run, staying committed to an AF method that gets better as hardware gets faster may prove to be a better choice than an approach that trades-off light capture for AF performance. But the S5’s performance, particularly in video, shows DFD is not there yet. The risk for Panasonic is whether these fast-readout sensors and powerful processors arrive before the majority of full frame buyers have already committed themselves to other camera systems.

There is also one fact to mention: Not having phase detection pixels on the sensor gets rid of the sometimes annoying “stripe” artifact.