[Luny Tune]

I see now in the pictures that the front element is concave, so apparently it's a design that is different from the classic scheme found in the old 50s. Similarly to how the Zeiss 55/1.8 ZA only has 7 elements in 5 groups, but from the block diagram it looks like an original kind of design, probably explaining its comparatively high price.

EDIT: updated with new (to me, anyway ) info.

Yeah, I was gonna reply with that info actually, but I don't really know much about lens design. I just noticed that it does indeed have a concave front element like the 55 (the 35/2.8 does too), 9 aperture blades, same filter size and as far as I can see pretty much the same size front element. It's a little lighter though, so it's probably made of the same material as the 35/2.8. Fine by me, but the 55 does feel very sturdy with it's metal construction and ain't heavy at all.