06-30-2017, 07:01 AM
Quote:The reason for that is the size of the image the AF sub mirror can intercept. So for OVF shooting you always have a more central placement of AF points.
Contrary to the D750, the 6D mk II does have PD AF in live view too, which is smooth and fast and has 80% frame coverage.
Well, yes that's why I can't see great FF AF coverage,...... even the D5, although with slightly larger spread, is limited.
What "was" the "ace hand" of the DSLR beating ML in all ways with AF, will in the end be it's limitation, as I doubt in the near future whether we will ever see a FF DSLR have decent coverage, while the A9 covers over 90% of the frame.
I notice that on the D500 with the Tamron 150-600mm at 600mm the AF struggles on the outer edge upper and lower points to focus at F6.3 where the 500mm F4 doesn't! No doubt the oblique angle of light at the edges of a FF AF array would aggravate the problem even more if they tried to cover the whole frame, as well as causing edge inaccuracy, something that the APSc format has few problems with.
No doubt that the 6DII beats the D750 in video. But they just wouldn't give people 4K and when they did in the 5DMK IV it was with motion Jpg just to be awkward, just like the single card slot in the 6DII. (and no headphone socket.....the expression "the halfpenny of tar that sunk the the ship" springs to mind here)
I just don't know why Nikon doesn't get on their case with on sensor PDAF, Canon has such an advance there which could go some of the way to explain Canon's continued lead in the market even in spite of Nikon using Sony's superior sensors. Canon also benefits from their own home grown sensors which gives them the ability to be in total control of their own game.
Either way between Canon and Nikon they both cripple their feature list one way or another.......
Sony must be delighted!