The Russar 20 mm is a charming, old-fashioned lens that works very good even in the corners.
The formfactor is fantastic and allows me an unobtrusive style. I use Voigtlander 21 mm viewfinder.
I have a 18mm coding (WATE), but 21 mm (Elmarit) gives less purple fringe on a color camera.
Please post your own Russar pictures
and enter my magic circle