Collapsible Summicron 50mm f2. Leica screw mount. Leitz product code: SOOIC. Serial number: 1,340,000. Manufactured in 1956. Marked in feet.

This is a classic large-aperture lens from Leitz. It was introduced as the third-generation high-speed standard lens following the Summar and Summitar. Its overwhelming resolution caused quite a stir in the photography industry at the time and played a crucial role in the rise of Leitz's prominence, particularly with the subsequent launch of the Leica M3.

Although this collapsible Summicron has been produced in relatively large numbers, many specimens have suffered damage to the glass due to cleaning marks or deterioration of the middle element, making it increasingly rare to find one that can deliver its intended performance. This particular unit has a relatively good condition of the glass.

There is a minor repair mark at one spot on the base of the lens barrel and a few inconspicuous scratches on the helicoid ring. Aside from these, the collapsible portion shows minimal signs of use.
In October 2024, a full overhaul was performed, including focus adjustment. The aperture and helicoid operate with a smooth and pleasant feel. The rangefinder coupling works perfectly as well.
The front element has minor cleaning marks and some wear on the coating, but there is no fogging, and the glass condition is quite good for a collapsible Summicron. The coating is intact across the entire surface. Coupled with the precise rangefinder alignment, you can fully enjoy the characteristic rendering of the Summicron even at wide open.