Its a bit disappointing that they can't work on the standard SLR. The 40XS design is also apparently a fixed focus lens, please correct me if I am misunderstanding some of what I have read on this, which might be great for the video aspect but presents other limitations.
Pentax 40mm F/2.8 Interchangeable Lens
- Ultra low profile is only 0.36 inches thin at 1.8 oz.
- Fixed focal length 40mm prime lens is equivalent to 61mm in the 35mm format.
- Short 16 inch minimum focus distance.
- Maximum F2.8 aperture is ideal for existing light photography and creative depth of field applications.
- Nine rounded aperture blades produce extraordinarily smooth, natural bokeh.
- Pentax SP (Super Protect) coating on lens surface helps repel elements and aids in cleaning.
- Pentax KAF mount is compatible with current and past K-mount compatible cameras.
The new smc Pentax-DA 40mm F2.8 XS interchangeable lens is the world's thinnest interchangeable lens.* The new 40mm combines with the Pentax K-01 camera body to deliver a unique compact system camera that is perfect for photographers who are as keen on design as they are on performance. Together, the K-01 and this 40mm lens system mark the intersection where high technology and high design meet.