I own a mint M mount 50mm f/2.0 Collapsible Type I. The lens performs best at f/4, drawing classic, beautiful portraits. The performance at f/2 is flat in contrast. The performance is just behind the Summicron DR at f/2.8. At f/2.8 to f/3.5 it has low to medium contrast and is the equal of the DR, Type II. The lens is small but not as small as an Elmar. An old Elmar 50mm f/3.5 has lower performance at wider apertures since it is 4 elements in 3 groups. The sweet spot for the Elmar f/3.5 is f/8 vs f/4 for the Cron. Performance improves in the Elmar f/2.8 but at f/4 my guess is the collapsible is better. Between a Summitar, Summicron and Elmar an older Cron is the best choice for B&W portraits. If using color film I suggest a Summicron Type III or IV. Learn more at kenrockwell.com
To appreciate the 1950/60 older glass the lens must be clean. After 60 to 65 years mint optics are hard to find.
Image outlines for the collapsible at f/4 are sharp and rounded, midtones creamy, and backgrounds oh so smooth. The lens iris is a circle.
Last edited by Richard Jepsen; 12-12-2012 at 03:54 PM. Click to view previous post history.