Olympus OM Zuiko 35mm f/2.8

Introduction

Olympus used to manufacture five main groups of wide angle lenses for its popular OM system. These included 18mm, 21mm, 24mm, 28mm and 35mm primes. The 35mm version was offered as an f/2 as well as f/3.5 variants. Olympus used to manufacture the range of OM lenses up until 2002 , but eventually abandoned in favor of the all digital Four Thirds system. The 35mm f/2.8 version of the lens is widely available on used markets like eBay, with good copies selling for ~US$70 (as of March 2008).

The optical construction of the lens consists of 7 elements in 6 groups, and what is quite surprising here is (as well as with many other Olympus lenses in general) is that Olympus managed to squeeze such a relatively complex for a prime formula into such a tiny lens - it measures only 33 x 59mm (1.29 x 2.32in) and weighs 180g (6.34oz). The lens extends a little bit when focusing towards closeup, making the lens a little bit longer. The build quality of the lens is superb, which is characteristic of pretty much all Olympus lenses of that time. The lens barrel as well as the aperture ring are all metal, while the focus ring is fully rubberized.

Olympus OM 35mm f/2.8 is a fully manual lens, so while it can be used on the modern Olympus digital SLRs (through an OM to Four Thirds adapter), you will end up manual-focusing it. The lens does not have any electronic contacts on the mount, so lens information is not going to be transmitted into EXIF of your camera. The minimum focusing distance is 30cm (0.98ft) and the minimum supported aperture is f/16. The lens accepts 49mm screw-in type filters.

Image

Since the lens was originally developed for conventional 35mm cameras, when used on an APS-C body with 1.6x crop factor, the field of view of the lens will be similar to that of a 56mm lens on a full frame body, while when used on a Four Thirds system, its field of view will resemble a 70mm prime.

 

Summary
Lens Composition 7 elements in 6 groups
Angular Field 63 degrees
Minimum Focus 30cm/0.98ft
Focusing Action MF
f-stop Scale f/2.8-f/16, manual
Filter Size 49mm
Lens Hood N/A
Weight 180g/6.34oz
Dimensions 33x59mm/1.29x2.32"
Lens Case N/A

 

Field Tests

Olympus OM Zuiko 35mm f/2.8 showed what I consider a typical for wide angle lens performance in the field (for wide angle primes that is). Visually, center performance was quite decent on both APS-C as well as FF cameras, whereby border quality lagged at wider apertures, more so on a full frame body then on an APS-C one. Like its faster f/2 version which I tested recently, OM Zuiko 35mm f/2.8 struggled around borders (on FF camera) and while stopping down helped improve the quality, borders did not seem to improve significantly at f/4, making f/5.6 the largest aperture that was producing acceptable quality across the frame.

 

ISO 400, 1/40, f/2.8, 35mm (Canon 5D)
ISO 400, 1/40, f/2.8, 35mm (Canon 5D)

 

When used with wide open aperture, the lens produced OOF highlights that were round and mostly uniformly lit, but with distinct bright outline (so far this seems to be pretty typical for most wide angles). Contrast transitions in near/far OOF areas remained rather harsh (harsher then what I'd like to see in a good portrait lens). The lens did not show any major sign of double-edging around blurred objects.

 

Vignetting @ f/2.8 - full frame vs 1.6x crop (35mm)
Vignetting @ f/2.8 - full frame vs 1.6x crop (35mm)

 

On a full frame camera, Olympus OM 35mm f/2.8 showed  quite a noticeable vignetting at f/2.8. Vignetting continued to persist at f/4, albeit at a lower level but became negligible at f/5.6. The lens behaved better on an APS-C body, taking advantage of a reduced frame coverage of a smaller sensor and at f/2.8 vignetting is barely noticeable and by f/4 it is practically gone. Considering that a Four Thirds system will have an even smaller sensor, vignetting should not be a problem there at all.

At wider apertures, Olympus OM Zuiko 35mm f/2.8 produced images that carried pretty low level of contrast, making images look a bit washed out (another common characteristic this lens has with its faster cousin). Contrast levels remain low until about f/5.6-f/8, which again might not be acceptable to some users. The lens produced some color fringing (lateral CA) mostly around borders throughout the aperture range. It also fell prone to some flare with wide open aperture and showed a minor degree of barrel distortion.

 

ISO 100, 1/1600, f/2.8, 35mm (100% crop)
ISO 100, 1/1600, f/2.8, 35mm (100% crop)
Olympus OM Zuiko 35mm f/2.8 image gallery...

 

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.

 

Four Thirds: Coming soon...

 

Canon APS-C: The lens showed pretty solid performance in  the center. Image quality was outstanding straight from f/2.8, and even improving slightly at f/4 and beyond. Not too shabby and nothing to complain about. Performance around borders is a different story though. Image quality around  borders lags center quite noticeably at f/2.8. Results here are mediocre at best. Things improve a bit when stopped down to f/4 and here border performance reaches decent levels. By f/5.6 border quality reaches quite an impressive level and stays at these impressive levels through the rest of the aperture. At its peak in the f/5.6-f/11 range, the lens  is capable of producing outstanding 19in and decent 24in prints, which is comparable to the resolution of some of the better wide angle primes out there. Conclusion? Prepare to stop down the lens to at least f/4 to achieve better overall results. Is this unusual? No, since most wide angle lenses do produce softer results around borders at wide open apertures. Still, one can wish...

 

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  on an APS-C body was more or less under control, with CA in the center averaging ~0.5px at f/2.8 and gradually dropping with stopped down aperture. CA around border was slightly higher, but still manageable, averaging ~0.8px across the tested aperture range.

 

Chromatic Aberration (APS-C) @ 35mm
Chromatic Aberration (APS-C) @ 35mm

Here are 100% crops of image borders taken with a Digital Rebel XTi at f/2.8 and f/8.

 

Image borders @ 35mm (100% crop): f/2.8 vs f/8
Image borders @ 35mm (100% crop): f/2.8 vs f/8

 

Canon FF: Unfortunately, Olympus OM Zuiko 35mm f/2.8 did not hold its ground on a full frame camera. But first thing  first. Center performance  continued to impress, with results remaining  top notch throughout the tested aperture range. So far, so good. But when it comes down to border performance, the lens simply falls apart at wide aperture settings. At f/2.8 image quality around borders is just plain inadequate. Performance improves a little bit at f/4, but when I say improves, I mean it goes from being inadequate to being mediocre. Only at f/5.6 performance around borders gets to solid  levels. Conclusion? Too little and too late - f/2.8 is practically unusable unless you're willing to tolerate very soft results around borders. Even f/4 is not much better. So why bother then?

 

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

Olympus OM 35mm f/2.8 showed minor level of barrel distortion. At -0.829% distortion can be noticeable but typically should not pose a major problem in general photography.

 

Distortion (FF) @ 35mm
Distortion (FF) @ 35mm

The lens showed slightly better handling of chromatic aberration on a full frame body. CA in the center was quite low, averaging ~0.3px across the aperture range and CA around borders never exceeded ~0.5px, generally averaging ~0.4px across the aperture range.

 

Chromatic Aberration (FF) @ 35mm
Chromatic Aberration (FF) @ 35mm

Here are 100% crops of image borders taken with a full frame Canon 5D at f/2.8 and f/8.

 

Image borders @ 35mm (100% crop): f/2.8 vs f/8
Image borders @ 35mm (100% crop): f/2.8 vs f/8

 

Alternatives

As mentioned earlier, Olympus used to manufacture another variant of the 35mm prime - Olympus OM 35mm f/2 . This particular lense offers very similar characteristics as its slower cousin, but is obviously slightly faster and almost 3 times more expensive. For slightly wider angle, you might want to consider three other OM lenses - Olympus OM 28mm f/2, Olympus OM 28mm f/2.8 and Olympus OM 28mm f/3.5. If you're willing to look at other then OM lenses, you might want to examine Carl Zeiss Distagon T* 35mm f/2.8 or its faster version Carl Zeiss Distagon T* 35mm f/1.4, both in Contax/Yashica mount, or their newest revision Carl Zeiss Distagon T* 35mm f/2 ZF/ZK for Nikon/Pentax mounts. Alternatively, you might also want to check Leica's Summicron 35mm f/2. For a side by side comparison of a number of 35mm primes, check out 35mm Challenge.

 

Recommendation

All-in-all, Olympus OM Zuiko 35mm f/2.8 is an average wide angle lens that does not show any major strength but has its own weaknesses. The main weakness is border performance at wider apertures - the lens does not improve in quality until f/5.6, which is a little bit too late. Other weaknesses that one should be aware of are vignetting (again on a full frame body), and pretty low level of contrast (again at wider apertures). There are obviously better performing 35mm primes out there, but virtually all such lenses would also cost significantly more. Hence one might still opt for Olympus OM Zuiko 35mm f/2.8, keeping in mind its shortcomings.