Introduction

Manufactured by Carl Zeiss Jena DDR, Flektogon MC 35mm f/2.4 was available in M42 universal screw, Exacta and B (as Practicar lens) mounts in both auto and electric versions. Manufactured up until reunification of Carl Zeiss Jena with Carl Zeiss of West Germany, the lens is more or less readily available on used markets, with good quality copies fetching about US$150 (as of August 2007).

The lens, which carries MC designation (standing for Multi-Coated), replaced its older and slightly slower single coated variant - Flektogon 35mm f/2.8. The optical design of the lens consists of 6 elements in 6 groups. The build quality of the lens is superb - barrel, focus and aperture rings are made of lightweight durable metal. The lens is pretty light and compact, weighing 250g (8.8oz) and measuring 51x61mm (2x2.4in), although the inner cam extends during focusing towards closup. The lens tested here was an electric variant, which supports both manual and fully automatic diaphragm action (controlled by an A/M switch on the side of the barrel).

Image

The minimal focusing distance is 19cm (7.48in) and the minimal aperture is f/16. The filter size is 49mm. On an APS-C camera with 1.6x crop ratio, the lens has field of view resembling that of a 56mm 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. You will end up operating the camera in manual or aperture priority modes with all but center weighted metering disabled.

 

Summary
Lens Composition 6 elements in 6 groups
Angular Field 62 degrees
Minimum Focus 19cm/7.48in
Focusing Action MF
f-stop Scale f/2.4-f/16, manual
Filter Size 49mm
Lens Hood N/A
Weight 250g/8.6oz
Dimensions 61x51mm/2.4x2"
Lens Case N/A

 

Field Tests

The lens performed quite well in the field, excelling in the center throughout the aperture range, but producing somewhat softer results around borders. The border quality was visibly soft at f/2.4, and improved with stopped down aperture. The lens has really short minimum focusing distance, which allows for some creative closeup photography.

 

Vignetting @ f/2.4 - full frame vs 1.6x crop
Vignetting @ f/2.4 - full frame vs 1.6x crop

 

The lens showed minimal level of vignetting with wide open aperture on a full-frame Canon 5D. Once stopped down to f/2.8 and beyond, vignetting becomes pretty much non-existent. Vignetting on an APS-C camera was non-existent straight from f/2.4. Color representation was pretty accurate and Flektogon MC 35mm f/2.4 did not exhibit color fringing. The lens also held up nicely against flare (the front glass element is pretty small for a wide angle lens, thanks to an inverted telephoto design) and did not show noticeable barrel distortion.

 

ISO 100, 1/2000, f/2.4, 35mm
ISO 100, 1/2000, f/2.4, 35mm
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 demonstrated outstanding performance in the center straight from f/2.4, with results staying consistently high throughout the tested aperture range. Border performance is somewhat soft at f/2.4 (not disastrous, but not awe inspiring either), but quality improves with stopped down aperture, reaching very respectable level by f/4 and outstanding level by f/5.6. At its peak from f/5.6 to f/11, the lens is capable of producing outstanding 19in and decent 24in prints. Conclusion? Performance is quite respectable for a wide angle lens and comparable to performance of some of some of the best lenses on the market.

 

MTF50 (Line Width/Inch on the Print) @ 35mm
MTF50 (Line Width/Inch on the Print) @ 35mm

 

Normalized raw MTF50 @ 35mm
Normalized raw MTF50 @ 35mm

 

Chromatic aberration was more or less under control on an APS-C camera. CA averaged ~0.4px in the center with wide open aperture but creeped up slightly around borders, where it averaged ~0.8px (with wide open aperture). Once stopped down to f/4 and beyond, CA becomes pretty much insignificant.

 

Image borders @ 35mm (100% crop): f/2.4 vs f/8
Image borders @ 35mm (100% crop): f/2.4 vs f/8

Canon FF: Flektogon MC 35mm f/2.4 continued to show outstanding performance in the center with a full-frame Canon 5D, but border performance suffers with aperture settings. Quality af f/2.4 is simply mediocre and while performance improves with stopped down aperture, it does not reach respectable levels until f/5.6. The lens achieves most balanced results in the f/8-f/11 range, where performance is top notch both in the center and around borders. Conclusion? Border performance with wide apertures is disappointing, but as I noted in my other reviews, majority of wide angle lenses struggle in similar situations, so Flektogon MC 35mm f/2.4 is not really an exception here.

 

Normalized raw MTF50 @ 35mm
Normalized raw MTF50 @ 35mm

 

CA was not a major issue on a full frame Canon 5D, averaging ~0.5px in the center and ~0.8px around borders with wide open aperture. As with the majority of lenses, stopping down helps reduce CA to pretty much non-existent levels.

 

Image borders @ 35mm (100% crop): f/2.4 vs f/8
Image borders @ 35mm (100% crop): f/2.4 vs f/8

 

Alternatives

The world of M42 mount lenses is choke-full of 35mm primes. And if you're willing to consider non-M42 lenses as alternatives to your modern dSLR, then the selection becomes rather unmanageable. Hence this list of alternatives is just a starting point that can help you get going. So, if you still want to stick with M42 mount lenses, you might want to take a look at the older, single coated version - Flektogon 35mm f/2.8.  Additionally, consider Asahi Super-Takumar 35mm f/2 or its slightly slower variant Super-Takumar 35mm f/3.5. Schneider's Curtagon 35mm f/2.8 and Voigtlander 40mm f/2 also come to mind. Outside of the M42 mount, take a look at Olympus Zuiko OM 35mm f/2 (which actually was also available in M42 mount) as well as Carl Zeiss Distagon 35mm f/2.8 (review) and Carl Zeiss Distagon 35mm f/1.4 both in C/Y mount. Finally, consider Nikon's Nikkor Ai-S 35mm f/1.4 and Nikkor Ai-S 35mm f/2 lenses.

 

Recommendation

Carl Zeiss Jena Flektogon MC 35mm f/2.4 is a very solid lens. The lens shows some weakness around borders at wide aperture settings, especially on a FF camera, but again, I have yet to see a wide angle lens that doesn't struggle here. Overall, this lens can easily compete with Carl Zeiss Distagon (C/Y) T* 35mm f/2.8 for your attention and bucks. One major advantage that could be quite valuable to some photographers is the close minimal focusing distance - it is actually shorter then on some dedicated macro lenses! Of course, all this assumes that you're OK using a fully manual lens.