Mamiya Sekor CS 135mm f/2.8, 5-blade, f-number from 2.8 to 16 mounted on XE1 with Fotodiox ZE-FX adapter. No aperture control. The lock on the Fotodiox ZE-FX adapter does not engage securely and the CS lens may unlock itself from the adapter. So be careful with this combo if you don't want the lens to drop from the camera.