Originally posted by LFLee "The new 40mm f/2.8 pancake lens is less than 1 centimeter thick and my understanding is that it will work only with the new K-01 body"
-- why old lenses can work on this body but the new 40mm don't wok with older body? hm.... it is can't AF on old body?
what could be the reasons?
Probably because the new lens protrudes into the body.
There not being a mirror in the K-01, lenses can be mounted a lot closer to the sensor, but the actual mount must be at the same distance as in a DSLR if the camera has to be compatible with the existing K-mount lenses.
So if you make a lens that sits half way into the camera body (where the mirror is in a DSLR), you can attach it to a K-mount and make it stick out much less (because only half sticks out). Of course, you could mount such a lens onto a K-mount DSLR if it weren't for the mirror which will be in the way.
Hence this lens will be K-mount but only for the K-01.
Wim