The aperture is oiled up. Shoud be easy to clean. But hey, just use it at f1.2.
Go not to the elves for counsel, for they will say both yes and no.
if you want swirly bokeh in a 35mm lens. this is it.
I had one of these and sold it for a small profit... it wasn't worth it.
AWESOME LENS, and very sharp at smaller apertures. Beautiful look as well; not as contrasty or saturated as an FD, but good in so many other ways.
If you are the big tree, we are the small axe