I have observed what he has mentioned.
Lenses that have been with me for years and totally ok since K7, suddenly not getting infinity focus when set to the infinity mark of the lens.
My M85/2 ended up focusing only to no more than 8m.
My personal thoughts are that the tolerance of the flange distance has been changed on the K1 and the result with old lenses with their own (looser) tolerances is a stack up tolerance issue.
Incidentally, my 'newer' FA limited are all fine.
So the 'new' tolerance is within stack limits of more recent lenses but might not be for old ones.
However, I don't blame Pentax for it.
The lenses ARE OLD.
Who knows what they went thru and what type of looser limits were film lenses based on (since film itself is not flat)
For me, I just sent the few affected lenses for a long overdue servicing and infinity adjustment.
Lenses came back cleaned, lubed and at infinity right where it is marked on the lens.
No reason to blame Pentax.
I'd blame them if they had this issue with still in production FA, DA, DFA lenses, but the rest is a 'no case' imo.
There are also a few threads out there on this wrt the Nikon D800 if the OP would like to google for it.
BTW, I promised myself, not to visit DPR Pentax sub section anymore..
Last edited by pinholecam; 07-21-2016 at 06:24 AM.