I would say that it's irrelevant. What kind of filters do you normally use? A circular polarizer? That's not going to work with this lens. The only thing I can see someone using on this lens would be some kind of neutral density filter. Practically anything else you can do in post.
5D Mk III, Elan 7e, Fuji X-E1, some old rangefinders
Tamron 24-70 2.8 VC, Canon 70-200 f/2.8L IS II, 400mm f/2.8L II, 100mm L IS Macro, Sigma 85mm, 50mm, & 35mm f/1.4's, Rokinon 14mm f/2.8, Canon 2x Extender II, Kenko 1.4x, 430 EX II, Elinchroms