Best Buy: Rokinon 800mm f/8 Mirror Lens For Select Olympus and Panasonic Cameras 91583715M
Has anyone tried the Samyang mirror lenses? - DSLR, Mirrorless & General-Purpose Digital Camera DSO Imaging - Cloudy Nights
Samyang Mirror Lens 500 mm 1:6.3 DX. Comparison with Rubinar 500/5.6. Review of the mirror-lens lens by Rodion Eshmakov | Happy
Samyang 500mm f/6.3 .... got this bad boi in the mail yesterday was pretty stoked to test it out... probably gonna get a ND filter for this guy next using a 92mm