Carl Zeiss Jena MC 29mm f/2.8

Introduction

Once in a while you see lenses with rather 'unusual' focal lengths - 58mm, 37mm, 83mm, etc. Carl Zeiss Jena 29mm f/2.8 clearly belongs to this category. Interestingly, while the lens carries Carl Zeiss Jena logo, it resembles another 29mm M42 lens manufactured by Meyer Optic of Gorltz DDR (later merged into VEB Pentacon). This is also the only Carl Zeiss Jena lens that does not carry a name after particular design like Flektogon, Sonnar or Tessar, which makes some to believe that the lens was actually manufactured by Pentacon towards the end of M42 production cycle and relabeled by Carl Zeiss Jena for export to Western Europe. I can't confirm whether this is truly the case, so if anyone knows the history of this lens, please drop me an email. The lens was discontinued in early 90s but is more or less readily available on used markets in Europe (less so in the US). Good copies of the lens fetch about US$80 on eBay.

The optical construction of the lens consists of 7 elements in 7 groups. Built quality is superb - metal body, rubberized focus and aperture rings, with no wobbling whatsoever. The lens is pretty lightweight and compact, weighing 240g (8.46oz) and measuring 5.6 x 5.2cm (2.2 x 2in), although the lens cam extend slightly when focusing towards closup. The minimum focusing distance is 25mm (0.82ft) and the minimum aperture is f/22. The lens accepts 55mm scew-in type filters and since the front lens element does not rotate during focusing allows using circular polarizers. On an APS-C cameras with 1.6x crop factor, the field of view of the lens is similar to that of a 46mm lens on a full-frame body.

 

Image

As with other Carl Zeiss Jena M42 manual lenses I used a generic Fotodiox M42 to EOS adapter without AF confirmation. I used camera in aperture priority mode, which along with the fully manual are the only two modes available to anyone using this type of an adapter.

 

Summary
Lens Composition 7 elements in 7 groups
Angular Field 73 degrees
Minimum Focus 25cm/0.82ft
Focusing Action MF
f-stop Scale f/2.8-f/22, manual
Filter Size 55mm
Lens Hood N/A
Weight 240g/8.46oz
Dimensions 56x52mm/2.2x2"
Lens Case N/A

 

Field Tests

Carl Zeiss Jena MC 29mm f/2.8 left me with a bag of mixed feelings - the lens was tack sharp in the center throughout the tested aperture range and extremely soft around borders (almost) with all aperture levels. I say almost because quality improves somewhat at smaller aperture levels.

 

Vignetting @ f/2.8 - full frame vs 1.6x crop
Vignetting @ f/2.8 - full frame vs 1.6x crop

 

The lens exhibited moderate amount of vignetting on an full-frame Canon 5D with wide open aperture. Vignetting is pretty much gone once you stop down to f/4. On an APS-C camera, the lens did not show any vignetting throughout the tested aperture range. Colors were a little bit washed out, and the lens fell prone to occasional flare. Carl Zeiss Jena MC 29mm f/2.8 also exhibited some color fringing in challenging lightning situations, both in the center as well as around borders.

 

ISO 100, 1/1600, f/2.8, 29mm (100% crop)
ISO 100, 1/1600, f/2.8, 29mm (100% crop)
Sample images coming soon...

 

Lab Tests

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.

 

Canon APS-C: The lens showed rather extreme range in performance. Image quality in the center was exceptional streight from f/2.8, reaching very impressive levels by f/4. Regretfully, border performance was simply disastrous with wide open apertures. And while border quality improves with stopped down, it does not reach acceptable levels until f/8. At its best, from f/8 to f/11, the lens is capable of producing outstanding 16in and decent 19in prints, which is can be considered pretty decent. Conclusion? It's expected that wide angle lenses would typically produce somewhat softer results around borders. The emphasis here is on the word 'somewhat', since Carl Zeiss Jena 29mm f/2.8 shows inadequate performance around borders even with this lower expectation. So if you care about border sharpness, this lens would be practically unusable with wide aperture settings.

 

MTF50 (Line Width/Inch on the Print) @ 29mm
MTF50 (Line Width/Inch on the Print) @ 29mm

 

Normalized raw MTF50 @ 29mm
Normalized raw MTF50 @ 29mm

 

Chromatic aberration was somewhat on a higher level with wide open apertures, averaging ~1.1px around corners and significantly less (~0.3px) in the center. CA is reduced with stopped down aperture and by f/8 reaches minila levels, averaging ~0.4px across the frame.

 

Image borders @ 29mm (100% crop): f/2.8 vs f/8
Image borders @ 29mm (100% crop): f/2.8 vs f/8

 

Canon FF: The lens did not fare well on a full frame Canon 5D. Image quality in the center remained quite impressive streight from f/2.8, but the border quality suffered even more when compared to the quality on an APS-C body (one would think it's not possible given already poor performance with wide aperture settings). Image sharpness around borders improves slightly by f/8-f/11, but even at those levels quality leaves room for improvement. Conclusion? With image quality suffering on both full-frame as well as APS-C bodies, Carl Zeiss Jena MC 29mm f/2.8 is not an awe-inspiring piece of optics.

 

Normalized raw MTF50 @ 29mm
Normalized raw MTF50 @ 29mm

 

Chromatic aberration remained on a relatively high level with wide open apertures, averaging ~1.1px around borders and ~0.4px in the center. Once stopped down, CA is drastically reduced and averages ~0.5px across the frame.

 

Image borders @ 29mm (100% crop): f/2.8 vs f/8
Image borders @ 29mm (100% crop): f/2.8 vs f/8

 

Alternatives

While there are a lot of 28mm wide angles available on the market, the benchmark rests with Carl Zeiss Distagon T* 28mm f/2.8 in Contax mount (review). This is easily the best 28mm prime I have tested to date, both in terms of image/build quality and price you pay. You might also want to take a look at Olympus OM Zuiko 28mm f/2.8 or its slower variant OM Zuiko 28mm f/3.5. If you insist on staying with M42 mount lenses, then take a look at Pentax SMC Takumar 28mm f/3.5 or Schneider Curtagon 28mm f/4. Both of these lenses are slower then Carl Zeiss Jena MC 29mm f/2.8, but exhibit very good image quality. Finally, if price is not an issue, then older Nikkor Ai-S 28mm f/2 and its slightly slower variant Nikkor Ai-S 28mm f/2.8 are two great performers.

 

Recommendation

Assuming you're considering using this lens as an alternative to your native mount wide angle prime, think again. Carl Zeiss Jena MC 29mm f/2.8 bears the Zeiss name, but does not live to the expectations typically associated with this brand name. Don't take me wrong, image quality in the center is simply outstanding. But this strength is offset by extremely weak performance around borders. Unfortunately, excuse that typically wide angle lenses show weakness around borders does not quite work here - the lens is that soft around borders. Naturally there are other factors that you should evaluate when considering a lens, but Jena 29mm does not quite shine in any particular area. So if you really, really want a wide angle alternative to your native mount lens, take a look at another Zeiss - Distagon T* 28mm f/2.8 in Contax/Yashica mount, or even Leica Elmarit-R 28mm f/2.8 - both of these lenses are more expensive then Jena 29mm, but both produce outstanding image quality.