Originally posted by robjmitchell Its been made with future FF cameras in mind, not 8 year old APS-C Cameras.
Indeed.
And it's not an "it could work either way" decision. Making the brand new D FA* 50mm f/1.4 backwards compatible with soon to be retired cameras means restricting it to a mechanism designed in 1975. The mechanical aperture linkage is slow, inaccurate, noisy, unsuitable for video, poses restrictions in lens design/aperture placement, and might introduce mechanical shock.
I'm sorry for everyone affected by this, but "I have an 8 years old camera" isn't strong enough to put up with the disadvantages.
The unfortunate thing is that the K-5 is such a nice camera... but it wasn't even made under Ricoh.