Carl Zeiss Jena Sonnar MC 135mm f/3.5, manufactured by Carl Zeiss Jena DDR up until early nineties, was available in M42 universal screw as well as B mounts, primarily in Eastern Europe. The lens was discontinued after reunification of Carl Zeiss companies, but is still readily available on used markets like eBay, with good quality copies going for about US$100 (as of August 2007).
The optical construction of the lens consists 4 elements in 3 groups. The build quality of the lens is quite good - barrel is all metal as is built-in lens hood. Focus and aperture rings are ruberrized, but the aperture ring feels a little bit flimsy. The lens is quite lightweight and compact for a medium telephoto lens, weighing 430g (0.94lbs) and measuring 5.1 x 8.9cm (2 x 3.5in), however the lens cam extends during focusing towards the closup, almost doubling the length of the lens. Like all Carl Zeiss Jena lenses in M42 format, Sonnar 135mm f/3.5 is a fully manual lens, with manual focus and aperture control, but has a pin for automatic diaphragm action (diaphragm mode is controlled an A/M switch on the side of the barrel.
The lens, which carries MC (Multi-Coated) designation replaced an older, single-coated variant - Sonnar 135mm f/4, also available in M42 and B mounts. The minimum aperture of the lens is f/22 and the minimum focusing distance is 1m (3.3ft). The filter size is 49mm. On APS-C cameras with 1.6x crop factor the lens has field of view similar to that of a 216mm lens on a full-frame body. To test the lens on Canon EOS body, I used a generic Fotodiox M42 to EOS adapter without AF confirmation.
|Lens Composition||4 elements in 3 groups|
|Angular Field||18 degrees|
|f-stop Scale||f/3.5-f/22, manual|
Carl Zeiss Jena MC Sonnar f/2.8 showed surprisingly (for such an old and simple lens design) results. Images taken with the lens were crisp and contrasty across different aperture settings. There was no visible degradation in border quality and the lens performed consistently throughout the tests.
Vignetting was practically non-existent throughout the tested aperture settings both on a full-frame Canon 5D as well as on APS-C Digital Rebel XTi. This does not come as a surprise though for a slower telephoto prime. The lens showed no barrel distortion but fell prone to minor color fringing across the frame. Color representation was pretty accurate (although I would say that the colors were a bit saturated) and the lens stood up well against flare.
|Sample images coming soon...|
Please note that MTF50 results for APS-C and Full-Frame cameras are not cross-comparable despite the same normalized [0:1] range used to report results for both types of cameras.
Two lenses were tested in the lab (serial numbers 150546 and 162006), both producing very similar results, with ~3% variance averaged across the tested aperture range.
Canon APS-C: Carl Zeiss Jena MC Sonnar 135mm f/3.5 showed outstanding performance in the lab. Images were sharp from corner to corner throughout the tested aperture range. More importantly, performance was even both in the center and around borders, which is a major benefit in any lens. Actually, the lens produced one of the most consistent results among medium telephoto lenses tested to date. With no peaks or dips in performance, the lens is capable of producing outstanding 19in and very decent 24in prints throughout tested aperture settings - quite an achievement even for a telephoto fixed focal. Conclusion? With outstanding results across the frame and across aperture range, this 20+ year old lens design still goes strong and would put to test any modern lens.
Chromatic aberration was quite low even for a medium telephoto prime, averaging ~0.3px across the frame with wide apertures and even less so once stopped down to f/5.6.
Canon FF: The lens showed top notch results on a full-frame body, closely mirroring performance seen on an APS-C camera. Image quality was outstanding and MTF results were evenly distributed across the frame. Performance degrades slightly towards f/11, but even then it remains on a very decent level. Conclusion? Carl Zeiss Jena Sonnar certainly shows consistency not only across aperture settings, but also across the image frame, which is what expected from good lenses.
CA remains relatively low even on a full frame Canon 5D, with CA not exceeding ~0.5px in the center and ~0.6px around borders with wide open aperture. Once stopped down, CA is reduced to insignificant levels.
Assuming you want to stick with M42 mount lenses, you might want to consider Carl Zeiss Jena's older Sonnar variant Sonnar 135mm f/4 or its close cousin Triotar 135mm f/4. Alternatively, you might want to take a look at Meyer Orestor (Pentacon) 135mm f/2.8 or its cousin 100mm f/2.8. No list of M42 lenses would be complete without Asahi Pentax lenses. Here you should evaluate Super-Takumar SMC 135mm f/2.8 and its slower variant 135mm f/3.5. Outside of the M42 mount, Carl Zeiss Sonnar 135mm f/2.8 in C/Y mount (review) is a solid performer as is Carl Zeiss Planar 100mm f/2 (also in C/Y) mount. Finally, you might also want to consider Leica's Elmarit 135mm f/2.8 and Olympus' Zuiko OM 135mm f/2.8 and 100mm f/2.8. The list goes on and on...
We might have stumbled on a diamond in the rough here. Carl Zeiss Jena MC Sonnar 135mm f/3.5 certainly delivers a lot of bang for the buck and has very few shortcomings (aside from being a fully manual lens that you need to adopt to your favorite dSLR that is). As a matter of fact, the only shortcoming that comes to my mind is it's relatively slow speed - f/3.5 is not going to win any prizes here. Nevertheless, considering its image and build quality, its compact size, light weight and its price, the lens should probably remain on the shopping list of anyone interested in finding a good bargain among alternative mount lenses.