Comparison
KMZ Jupiter-8 50mm f/2 vs Leica Summicron-R 50mm f/2
The KMZ Jupiter-8 50mm f/2 is a 50mm f/2 M39 (Leica screw) lens made 1950s-1980s, valued at $30 to $120 used. The Leica Summicron-R 50mm f/2 is a 50mm f/2 Leica R lens made 1964-2009, valued at $350 to $900 used.
Specifications side by side
| Specification | KMZ Jupiter-8 50mm f/2 | Leica Summicron-R 50mm f/2 |
|---|---|---|
| Focal length | 50 mm | 50 mm |
| Maximum aperture | f/2 | f/2 |
| Native mount | M39 (Leica screw) | Leica R |
| Production years | 1950s-1980s | 1964-2009 |
| Optical design | 6 elements / 3 groups, Sonnar | 6 elements / 4 groups, Double Gauss |
| Typical used value | $60 | $550 |
| Value range | $30 to $120 | $350 to $900 |
| Adapts to | Sony E, Fuji X, MFT, Canon RF, Nikon Z, L-mount | Sony E, Canon RF, Nikon Z, L-mount, Fuji X, MFT |
What actually differs
- Both open to f/2, so neither has a speed advantage.
- The KMZ Jupiter-8 50mm f/2 is cheaper. Typical used value is $60 against $550, a gap of $490 (roughly 9.2x). Ranges: $30 to $120 versus $350 to $900.
- Both are 50mm lenses, so framing is identical on the same sensor.
- The KMZ Jupiter-8 50mm f/2 is the older design; production began around 1950 against 1964 for the Leica Summicron-R 50mm f/2 (1950s-1980s versus 1964-2009).
- They use different mounts, M39 (Leica screw) and Leica R, so each needs its own adapter. Both reach infinity on mirrorless bodies with a plain mechanical adapter.
- Construction differs: 6 elements in 3 groups for the KMZ Jupiter-8 50mm f/2, 6 elements in 4 groups for the Leica Summicron-R 50mm f/2.
Which one to buy
On the catalog data the KMZ Jupiter-8 50mm f/2 wins on the $490 lower typical price, and the Leica Summicron-R 50mm f/2 gives up nothing measurable in return except its own rendering, described below. Condition and variant matter more than the spec sheet at these prices.
Minimum focus distance, weight, and measured sharpness are not in the catalog, so this comparison does not claim anything about them.