Leica Showcase Canon 5cm F2 Serenar

I picked this lens up for $50 at a Photorama Show from my favorite dealer. He knows exactly how rare it is, under 2000 made. This one was missing the infinity lock button, needed a CLA. I hade aspare release button from a parts 50/1.5, cleaned the helical, cleaned the front and rear surfaces, did not open it up.

This lens is a classic 1-2-2-1 double Gauss, very similar to the Leica Summar but the glass elements are wider diameter- closer to the Summitar. This is done to reduce vignetting. The lens uses 40mm filters, and is in a single-helical, collapsible mount. It is well made, and looks good for being almost 70. The surfaces are hard coated, some cleaning marks on this one- but nothing bad.

At F4,

by fiftyonepointsix, on Flickr

by fiftyonepointsix, on Flickr

by fiftyonepointsix, on Flickr

to my eye- much less flare than the Summar.
And at F2- "dig that wild-bokeh"...

by fiftyonepointsix, on Flickr

by fiftyonepointsix, on Flickr

This is Canon's first Fast-Fifty, made it's way onto the market in 1947, produced through 1949 when replaced by the 50mm F1.9 Serenar. You would think that nothing but marketing to beat Nikon's 5cm F2- but in addition to the slightly faster speed, the F1.9 version has a redesigned mount with double-helical.