The Olympus 12-40 mm PRO was the first lens released as a part of the M. Zuiko PRO series of Olympus Micro Four Thirds lenses. Slotting into the range above the M. Zuiko Premium range of prime lenses, the PRO lenses, according to the advertising spiel, represent the pinnacle of Olympus’ lens designs. Common characteristics include metal cladding, Olympus’ ZERO coating on all glass surfaces, environmental sealing, snap manual focusing rings, and a generally higher standard of fit and finish.
Due to the high initial demand for the lens, I waited a few months before purchasing my copy. I’ve now had the lens for about a year, during which time it has been my primary lens on my OM-D E-M5. Naturally, I’ve formed some opinions of it in that time, and this post will be exploring those in terms of its design, handling and image quality, followed by a summary of my conclusions, and my recommendations. As is customary, I won’t be getting too technical in this post – there are much better websites for that information.
The lens covers a 35 mm equivalent field of view of 24-80 mm, which compares to a typical 24-70 mm standard zoom lens on the larger format. The f/2.8 maximum aperture is constant throughout the zoom range, in line with the high level standard zooms of other systems. Unlike the high level zooms designed for other systems, the 12-40 PRO takes 62 mm filters, which are usually more affordable than the upwards of 72 mm filters generally required for a standard zoom on a larger format system (or even the original Four Thirds system).
It’s quite a handsome looking lens, in my opinion. It’s finished all in black, with engraved and inked markings (except for the focal lengths and distance scale), and a nice taper towards the mount. The control rings are differently sized, and have a different knurling pattern for zoom and focus which does upset the overall look a little, but has functional implications I’ll discuss later. The focus ring features Olympus’ snap focus mechanism, meaning that when it is pulled back, the camera is switched to manual focus, and a manual focusing scale becomes visible at the front of the lens. At the left rear of the lens is a “L-Fn” button, which is customisable from the camera menu. This is a very nice feature, as I’ve often found the E-M5 needs at least a couple of extra customisable function buttons.
Unlike the lesser lenses produced by Olympus, the lenses in the PRO series include a lens hood (as should all lenses, in my opinion). The hood has a metal effect rear end to co-ordinate with the body of the lens, but is otherwise made of thick plastic, with two large buttons to lock and unlock the hood from the bayonet mount on the front of the lens. The petal design gives the most effective shading of the front element possible, although due to the focal length range of the lens, is still too shallow to prevent a lot of wind-blown water from settling on the front element. The package is capped off with a thick plastic lens cap, with a spun metal finish on the front, and a centre-pinch type release.
The 12-40 mm PRO is a heavy lens compared to its fellow Micro Four Thirds standard zooms. However, on one of the DSLR-style bodies, especially with a battery grip, it doesn’t feel front heavy, and cradles in the hand quite nicely. Compared to a DSLR and standard zoom, the overall package is still smaller and lighter; the primary reason I bought into the Micro Four Thirds system to begin with. The extra heft of the 12-40 imbues it with a solidity that is often absent from small and lightweight lenses, although this is let down a little by a rattle between ~32-40 mm. This rattle is caused by the zoom mechanism, which operates by extending the front section of the lens, rather than shifting lens groups internally. It’s a catch-22, though: the rattle could be eliminated by switching to internal zooming, but internal zooming would likely result in a longer (and less wieldy) lens barrel. There is also a light abrasive noise from the lens barrel when it is extending and retracting, although I’m yet to see any ill effects on the weather sealing or image quality, and it’s not really noticeable in the field.
Getting the lens ready for use is a doddle. Thanks to the centre-pinch style of the lens cap, it’s very easy to get the cap on and off the lens with the hood fitted. The pinch buttons are, in fact, large enough to allow easy manipulation when wearing thick gloves. I’d like to see this lens cap design, in some form, extended to the rest of the Olympus lens range, as their outer edge release buttons are difficult to remove with lens hoods in place, and near impossible to use with gloves on if a lens hood is fitted. Speaking of lens hoods, the included one locks reasonably securely to the front of the lens, although the softness of the release buttons means that it may occasionally become dislodged in a bag. The hood can be stored backwards to reduce the space the lens occupies in a bag, although the lens will still be noticeably larger than any of the other Micro Four Thirds standard zooms.
Controls are well laid out on the 12-40, in the sense that they can be identified and operated largely by touch: the focus and zoom rings are distinguishable by their different size and knurling, along with a smooth finished depression between them; while the function button is located within a well defined plastic cutout on the upper left rear quarter of the lens. The control rings operate very smoothly, with positive feeling end stops for the zoom ring and the focus ring (when it is in snap-focus mode). It would have been nice to see engraved and inked markings for the focal lengths on the zoom ring, as I suspect the screen printed ones may wear off over time. This shouldn’t be an issue with the distance scale, which is recessed in use, and protected when not in use.
Snap-focus mode is accessed with little resistance, and quite soft stops when pulling the ring fore to aft and back again. However, the lack of resistance can cause the lens to switch to manual focus when placing it in a camera bag, which can be irritating when pulling it out for a quick shot, although this may be rectified by changing the way the camera is being handled, or checking the focus ring position as it is brought up to the eye. When in manual focus mode, the focus scale is very clear, and I’ve found it quite beneficial late at night, where the viewfinder is often too dark to be able to focus by eyesight. Unfortunately, because of the lens’ variable focal length, a depth of field scale was not able to be included in the design.
Being on the top left rear quarter of the lens barrel, and positioned sensibly far away from the lens mount, the L-Fn button falls naturally under the left thumb when shooting. I have mine programmed to depth of field preview, and find that it is very quick and convenient for this purpose.
Image quality with the 12-40 has never been anything short of fantastic. Shots have a decent level of contrast, helped by the inherent flare resistance of the ZERO coating and good design of the lens hood. Flare is very well controlled, and there is very little loss of contrast from veiling, even when a bright light source is aimed directly at the front element. Rendition of out of focus areas (bokeh) is generally very smooth, and the transitions between areas that are in focus and out of focus also tend to be smooth. However, when there is a lot of detail, such as mixed foliage and branches with some sun coming through, it can be a little rough in places. It’s by no means the roughest bokeh I’ve ever seen, but there are better options if smooth bokeh is a priority.
Sharpness levels are good, and generally uniform across the frame (to my eye). At f/2.8, it’s noticeably sharper than the peak sharpness delivered by the Olympus 12-50 mm, and on a par with the sharp primes of the M. Zuiko Premium series. The 12-40 sharpness peaks between f/4-f/8, with diffraction becoming noticeable at f/11, and far more pronounced at its minimum aperture of f/22. That being said, the very high initial levels of sharpness mean that at these smaller apertures, it still appears as sharp or slightly sharper than softer lenses (like the 12-50 mm) when they are shot at their optimal aperture. It’s one of the sharpest lenses I’ve ever owned or used, rivalling some of the Zeiss, Leica, and high end Nikon and Pentax lenses I’ve owned. As a testament to its sharpness, I have an A1 (594 x 841 mm or 23 x 33″) glass print of some flowers I photographed with this lens hanging by my desk, and it’s sharp even when viewed right up close.
Conclusion and Recommendations
The Olympus M. Zuiko PRO 12-40 mm f/2.8 is a well thought out lens. It’s controls are well placed and weighted, and the whole unit is assembled to a high standard, although some evidence of compromises in design are evident. Although it is heavier than typical Micro Four Thirds standard zooms, its image quality is, quite simply, excellent, with high levels of flare resistance, sharpness and contrast, along with generally smooth bokeh. It’s become my go-to lens for most applications, and has yet to disappoint me.
This section mostly recapitulates the recommendations at the end of my Olympus 12-50 mm “review”:
- The 12-40 is untouchable in the Olympus standard zoom range for image quality. If you want the best out your Olympus Micro Four Thirds camera in this focal length range, and the convenience of a zoom, this is the lens you want.
- The 12-50 is not as good as the 12-40, but is still a decent lens when used within its limitations. I think it’s best suited as an “expendable” backup, for travelling light, or for getting away with buying smaller filters.
- The Olympus M. Zuiko 14-150 II, being weather sealed and covering a very wide range, looks to be the best overall option from Olympus for travelling light, or avoiding having to change lenses.
I usually use my 12-40 in concert with the Olympus 60 mm f/2.8 Macro and 75-300 f/4.8-6.7 II, the latter lens under a rain cover if conditions are poor. This covers almost any situation I’m likely to find myself in, and offers good quality throughout the range, reliably producing good 305 x 455 mm (12 x 18″) glossy prints.
One new recommendation I will make is the Panasonic Lumix X Vario 12-35 mm f/2.8 lens, espeically for Panasonic body users. My brother in law uses Panasonic bodies, and finds that since they don’t have in body stabilisation, a stabilised standard zoom was essential. The image quality is similar to the Olympus 12-40, although the lens is lighter and lacks 5 mm of reach at the long end (which isn’t much in practice). It’s a good weather-sealed option, and may be a better fit for your needs than the Olympus 12-40.