Olympus 12-60mm f/2.8-4 ED SWD Zuiko Digital

SLRgear Review
April 13, 2009
by Andrew Alexander

The Olympus 12-60mm ƒ/2.8-4 ED SWD was announced in October 2007, coincidental with their E-3 flagship digital SLR body. The lens is designed to fit the Four-Thirds body mount specification, meaning it will mount also to Leica and Panasonic bodies. The lens is one of the first designed by Olympus with its new SWD (supersonic wave drive) autofocusing technology, enabling fast and silent autofocus. Olympus claims that when this lens is mounted on the E-3 body, it provides the fastest autofocus on the market.

The Four-Thirds specification employs a 2x ''crop factor,'' producing an effective field of view of 24-120mm. The lens uses a variable aperture, meaning the maximum (largest) aperture will decrease as the lens is zoomed out. The following table sets out the changes:

The Olympus 12-60mm ƒ/2.8-4 ED SWD lens comes with a petal-shaped lens hood, accepts 72mm filters and is available now for approximately $950.

Sharpness
The 12-60mm lens is very sharp, though we did have some issues in the lab getting it to produce optimally sharp images. I'll go into further detail in the autofocus section. Let's look at the results.

The lens produces extremely sharp images, even shot at its widest aperture; central sharpness is in the 1-1.5 blur unit range, and wide open there's just a slight amount of corner softness: around 2 blur units. Stop down to ƒ/4, and this corner softness is almost completely eliminated. Optimal sharpness is achieved by ƒ/5.6, though we're talking about fractions of a blur unit in the corners. Diffraction limiting appears to set in at ƒ/8, though again these are still very small numbers - optically, the lens is still producing images in the 1-1.5 blur unit range all the way to ƒ/16.

Image quality stopped down is still very good: around 2 blur units across the frame at ƒ/16, and about 3 blur units across the frame at ƒ/22. Things get slightly uneven at ƒ/22, but nothing to write home about.

All in all, excellent results for sharpness here.

Chromatic Aberration
Chromatic aberration is optimized for the mid-range (~35mm) of the lens, with slightly noticeable results showing in the corners at the wide and tele ranges. Average CA performance throughout the frame is good, less than 3/100ths of a percent, meaning that if you see CA, it'll likely be in the corners.

Interestingly, CA increases as you stop down below 35mm, but is more prevalent with larger apertures above 35mm.

Shading (''Vignetting'')
Corner shading isn't too big an issue with this lens. The only remarkable numbers we note are with the lens set to 12mm and ƒ/2.8 - at this setting the corners are 2/3 of a stop darker than the center. Wide open at 19mm and 24mm, the corners are a 1/3 of a stop darker. At any other setting, corner shading is a quarter stop or less.

Distortion
The lens contends well against distortion, but given the wide / tele range it has to cover, it's not surprising to find evidence of some. Barrel distortion is prevalent in the corners below 17mm; after this point we start to see pincushion distortion in the corners. At 15mm the corners transition from barrel distortion to pincushion distortion. The numbers aren't terribly huge in any case: at 12mm, we see +0.75% barrel distortion in the corners. At 19mm pincushion distortion is at its highest: -0.25%, which is really not much at all. On average there is a very slight amount of barrel distortion throughout the frame, just under +0.1%, but this shouldn't be an issue unless you need to have absolutely straight lines in your image.

Autofocus Operation
Olympus advertises the 12-60mm as the world's fastest autofocus lens, when mounted on the E-3 body. We use an E-510 as our Olympus test body, and even then we can say it is a very fast lens for autofocus, and virtually silent. As regular readers may know we don't use autofocus in our lab tests, but we do for our sample scene shots, and for these we had a very hard time getting consistently accurate focus. We upgraded the firmware on both our camera and the lens, but it didn't really help: we finally ended up using live view and 10x magnification to get acceptable results. Obviously, this problem could be related to our lens, camera, or both, but it's worth mentioning only in that you may want to try before you buy, if possible.

(A side note: Reader Urs Shenker wrote in to let us know that there is a product advisory out for this lens, alerting owners to possible focusing issues, and offering a free repair if you encounter a problem. We checked to see if our lens fell into the range of affected serial numbers, but found that it did not. (Ours was serial number 230005175, while the affected range is 230005416 to 230010688.) So, as noted, the problem could well be with our E-510 test body, which has seen a lot of use by now, and has never been serviced. Still, thanks to Urs for pointing this out to us. For any of our readers who own this lens and see any focusing issues, check your serial number against the range mentioned above.)

Olympus has designed this particular Zuiko model more conventionally in comparison to its more recent lenses: it's manually coupled to the body, so you can focus manually while the camera is powered down. Autofocus results can also be overridden at any time by just turning the focus ring. As well, attached 72mm filters don't rotate during focus or zoom operations.

Macro
The 12-60mm provides respectable macro performance, with a 0.28x magnification and a minimum close-focusing distance of 25cm (just under 10 inches).

Build Quality and Handling
The lens is of plastic construction, but solidly built; there is no flexing or rattling to speak of. As part of Olympus' lineup of ''High Grade'' lenses, the construction of the lens makes it resistant to dust and water. The appearance of the lens is an all-black, semi-smooth finish except for a two-tone blue/silver ring near the end of the lens barrel. The lens has no buttons or switches on it at all; everything is controlled from the camera. A windowed and recessed distance scale is provided in between the zoom and focus rings, with markings in feet and meters, but there are no depth of field markings or infrared index. The zoom ring is located near the camera end, and the focus ring is located at the far end of the lens. Both rings use the same soft rubber material but with different ribbed patterns. The lens mount is metal, and the 72mm filter threads are plastic.

The 7/8-inch wide zoom ring uses a lined pattern running parallel to the length of the lens, but the thick lines are broken up into boxes; it's easy to tell the rings apart just by feel. A ninety-degree turn zooms the lens through its range of focal lengths. There is a nice resistance to the ring, eliminating the possibility of zoom creep. There is a fair amount of lens extension as the lens is zoomed out to 60mm: the lens gets 1 3/4 inches longer, adding 75% to its total length.

The focus ring is 3/4 wide and uses a ribbed texture to differentiate it from the zoom ring. The ring turns about 90 degrees to go through its entire focus range, and it could be that the short focus throw contributes to its quick speed. The ring provides soft resistance through its focus range, making it nice for manually focusing, and an increase in resistance at either end alerts you that you're at either infinity or close-focus. The focus ring can continue to be turned, however. The lens will focus slightly past infinity.

The lens comes with a LH-75B petal-shaped, bayonet-mounted hood. The hood ribbed on the inside to reduce flare, and adds 1 1/2 inches overall to the length of the lens. The hood reverses onto the front of the lens for easy storage.

Alternatives

Unfortunately, there really aren't many other options in this particular body mount and zoom range.

Olympus 14-54mm ƒ/2.8-3.5 II ~$600
A fair bit less expensive than the 12-60mm, the 14-54mm also produces very sharp images, perhaps a hair less than than the 12-60mm. The cost here is a lens that has slightly less focal range, though it is uses Olympus' latest technology. Chromatic aberration and distortion are slightly better controlled, light falloff is slightly worse.

Sigma 10-20mm ƒ/4-5.6 EX DC HSM ~$500
This lens is one of the few that Sigma produces for the four-thirds mount, and isn't really comparable to the 12-60mm except for its wide-angle coverage. It's hard to do a direct comparison as our test for this lens was done on the Canon 20D, using a 1.6x crop sensor, but a little creative interpretation suggests that it would be nicely sharp on Olympus 2x sensor bodies. CA is relatively high, typical for ultrawide angle lenses, and distortion as well as light falloff are also less controlled in comparison to the Olympus 12-60mm.

Conclusion
There's not much more to say about this lens for which our tests don't speak for themselves - the lens is a winner optically, producing very sharp images even wide open. Chromatic aberration is well-controlled, light falloff is minimal and image distortion is better than typical for the range of focal lengths the lens has to cover. It's superfast to autofocus, though we had difficulty using the lens to autofocus for our test scenes. This could certainly not be typical of the lens: your mileage may vary. When everything works though, it works beautifully; the lens is definitely worth the price premium.

Sample Photos

The VFA target should give you a good idea of sharpness in the center and corners, as well as some idea of the extent of barrel or pincushion distortion and chromatic aberration, while the Still Life subject may help in judging contrast and color. We shoot both images using the default JPEG settings and manual white balance of our test bodies, so the images should be quite consistent from lens to lens.

Still Life shot

VFA target

As appropriate, we shoot these with both full-frame and sub-frame bodies, at a range of focal lengths, and at both maximum aperture and ƒ/8. For the ''VFA'' target (the viewfinder accuracy target from Imaging Resource), we also provide sample crops from the center and upper-left corner of each shot, so you can quickly get a sense of relative sharpness, without having to download and inspect the full-res images. To avoid space limitations with the layout of our review pages, indexes to the test shots launch in separate windows.