17/2.8 Peleng A (Belomo)
Full-frame Fisheye from Belarus, with nice "Рыбий Глаз" designation.
Build like a tank (or rather hand grenade)?
Better flare control than in popular Zenitar 16/2.8.
Preset construction based on Helios-44-3 body.
Does need a UV filter screwed to the back to achieve infinity.
GREAT performer, pretty usable on digital.
cons:
HEAVY.
I've sold one to force myself back to using my EOS kit 18-55zoom as it weights nothing in compare to Peleng and is not as bad (nor as fun) :(.