[miro]

In order for the camera to take a picture or make a movie, the mirror must be up (unless it's the Sony SLT system, with the permanent mirror). During that time, "normal" PD AF does not work. So, it does not allow for continuous AF in movies, and even when taking pictures, if you shoot series, as long as the mirror is up, AF cannot track. So even for photography, when continuous tracking is desired, such a new system can provide benefits. 

In theory at least, the new system now has many many more AF sensors compared to the traditional PD AF, which is limited to selected points determined by where the AF sensors are located.  

Thnaks,

Tracking moving object could be beter at least in theory. AF cover area could be advantage for someone.

Honestly Im tired to read canon advertizing about this revolutionary??? system. They sounds like the Nikon 1 advertisement one year ago.

Back to the really techical part. I have questions

1. what is the base distance in canon 70d hibrid PD?

2. Is it constant across focus