A Makinon 500/8 Catadioptric or "Reflex" lens. Fixed f/8 aperture with threaded rear barrel and rear filters. The adhesive which bonds the secondary (front) mirror to the lens surface appears to have suffered some degradation at some point, although the mirror does appear firmly fixed. I have mounted this on an Autoreflex body and it does produce a usable image, likely somewhat softer than normal. It is certainly tolerable for casual film photography.
If you're the sort of person with an optical workbench that has access to optical adhesives and specialty solvents, and can collimate a lens, you can absolutely repair and tune this; however, I'm not sure it would be worth your while.
Condition Summary:
- No scratches
- Possible traces of mildew or fungus - whatever it is, it's long gone and doesn't look like the usual suspect
- Secondary/front mirror adhesive is degraded
- Case smells vaguely of mildew
- Previous owner attached a tether to the cap
What you get:
- Makinon 500/8 Catadioptric Lens, S/N 827603
- Original case with filter carrier
- ND1, ND4, and 1A ("Skylight") filters
- Filter insertion and removal spanner