Originally posted by normhead So, now image you have a 36x24 with pixel shift and that you don't need a 645z. I wonder if the next 645 will have pixel shift.
Although it is true, you can produce levels of detail that are largely invisible to the eye. Printing at 300 DPI you could certainly do that. People can resolve up to 600 DPI, from 8 inches away, if they look really close. But from a normal viewing distance, most can't tell the difference between 72 DPI and 150 DPI.
If the added detail is in fact a layer of detail that is not easily seen, then there would be no advantage to going to an FF instead of a K-3. I've suspected we reached that point with a K-5, and some experiments have backed that up for up to 24x36 prints.
There's not a lot of difference between, K-3 and K-5 in the actual images they produce. The K-3 tends to shine in AF, burst mode etc. I suspect the FF will be more of the same. More focus points, faster AF, better tracking, not so much in the images but in the ease of getting them.
SO, I agree, you may not feel a 36x24 sensor is necessary for IQ, but a camera is a lot more than final IQ. One of the things I like about Pentax is I can compete in end product with anyone out there, without the expense of their equipment. But, there are serious advantages to other systems as to the ease of getting those images.
Every point you make here is excellent, but maybe not in the way you intended....
The added detail is not easily visible, depending upon your print size. having shot the D810 and 5DIII and 6D, I am 100% APS-c now. There really is no practical advantages of FF for me. (And I print 30x40 inches a lot!)
A camera IS a lot more than final IQ. FF's are BIGGER and HEAVIER and MUCH more expensive. After 8 hours photographing a wedding, or 2 hours hiking with a camera backpack, I want as small and light as I can get that still gives me professionally competitive IQ. That's most APS-c current cameras. Now I want the one with the smallest and lightest lenses: There goes Canon and Nikon out. If I want fast lenses, there goes Pentax. If I want a DSLR with fast small WR zooms, Pentax is a WINNER!!! If I want a set of FAST primes, Fuji wins.
Guess what? I've got a Pentax system with fast zooms and flashes, and a Fuji system with only their fast primes. I shoot each about 50/50 these days. The only thing the Fuji system is really doing is showing me the few small gaps in Pentax's excellent lens range. A 16mm 1.4, 23mm 1.4, and 35mm 1.4 APS-c lens set form Pentax and the Fuji's would be GONE!
Pentax could have carved a real niche for themselves as the ONLY APS-c based Pro DSLR with a full set of small fast APS-c fast primes. They are SOOOOO CLOSE!!! The reason Fuji sales are up is because they have the lens set, not necessarily the cameras pros want to shoot. Love Fuji's lenses, not that big a fan of mirrorless. My preferred system right now is the Pentax with the fast zooms. But when that gets too heavy I am glad to switch out to the Fuji with the small fast primes.
As for Pixel shift, a straight well executed non pixel shift 24 mp image is going to probably deliver everything most people need out of an image. PS is nice to play with, but even without it, the K-3II resolution is spectacular.