Dont know if you all have noticed that, but Irix now has a new 150mm f2.8 macro coming out in PK mount :-)
The Irix 150mm f/2.8 MACRO 1:1 : My Irix
Specifications
Compatible sensor size 35mm “Full Frame” and smaller
Focal length 150 mm
Maximum aperture F2.8
Field of view 16⁰ (diagonal)
Range of focus 0.345 m (0.92 ft) – ∞
Focus setup manual
Focus ring rotation angle 270 degrees
Magnification ratio 1:1
Minimum focusing distance 0.345m
Aperture range f/2.8 – f/32
Aperture control via camera
Number of diaphragm blades 11 rounded aperturę blades
Lens construction 12 elements in 9 groups (4x HR, 3x ED)
Filter size φ77 mm
Weight 840g
Corresponding Mounts Canon EF, Nikon F, Pentax K
Dimensions 87 x 135 mm (without tripod collar and lens hood)
Lens hood Detachable
Additional features Focus Lock ring
Detachable tripod collar
Sealings Front element (1 O-ring)
Focus Lock ring + Focusing ring (3 O-rings)
Bayonet mount (1 O-ring)