Thehas a lot to live up to.
Since it was announced, it's had Micro Four Thirds (MFT) aficionados salivating: a fast and constant f/2.8 weather-sealed wide zoom (24-70mm equivalent) with optical image stabilisation (OIS). A professional-spec lens to deliver pro performance, it seems tailor-made to show what the MFT format can really do.
So who was I to argue when CNET Australia let me borrow one for a travel shoot in Far North Queensland for two weeks?
I was one of the first to adopt thein Australia, so I was keen to compare the field experience of shooting with a Canon for many years, as well as other larger-sensor cameras. All shooting for this project was done with a single OM-D E-M5 body, so there may be some difference in the performance with a Panasonic G-series camera.
The 12-35mm costs a hefty AU$1599, and performance would be expected to match this pro price point. I generally shoot with primes, usually the Panasonic 14mm f/2.5, 20mm f/1.7 and Olympus 45mm f/1.8, so a single lens covering nearly all of these focal lengths and promising similar (or better) image quality would be super convenient, despite costing nearly twice as much as those three primes combined. Rather than conducting a boring and subjective cost-benefit analysis, I'll keep my one-line assessment brief: it's the best all-purpose lens currently available for the MFT format, and worth the expense.
Build quality is superb. It's a compact but chubby beast when at its widest focal length of 12mm (24mm equivalent), and not too imposing when racked out to its longest length (35mm, or 70mm equivalent). Made from hard plastics, with metal accents around the weather-sealed mount, the lens looks and feels great, and is perfectly balanced for size and weight on the OM-D. It feels even better with the Olympus PLB-1 battery grip attached. Panasonic would do well to provide more info on the weather sealing, though, particularly as many buyers will be interested in this lens to go with the weatherproof OM-D. If it's just the mount on the Panasonic that's protected, fear of dust or water intruding via the lens barrel may limit the appeal to true "all-weather" shooters.
Having said that, I had no issues in a range of environments, from bone-dry beaches to humid tropical rainforests, in rain or in blazing Australian sun, shooting 10-12 hours each day. My batteries ran out before the lens showed any signs of stress, shooting through high-fps action sequences and tripod-mounted manual focus, and being dragged in and out of hot vans or air-conditioned rooms.
With the lens mounted to the camera all day, every day for two weeks, I felt no fatigue in my wrists, arms or neck. Even with a hotshoe-mounted flash, the size advantages of the MFT format aren't nullified by the lens. Also, the front element doesn't rotate during focus, making filter use hassle free.
Autofocus is lightning quick and super accurate in S-AF mode, but slows in Continuous/Tracking modes with the OM-D, and also once the light drops significantly. Of course, judicious choice of aperture handles action sequences (in other words, choosing a depth of field to sharply cover the area in which the subject is moving, rather than relying on the camera to re-adjust focus quickly enough). Clattering away at 9 frames per second with tracking, I had no trouble capturing skydivers or kite surfers, but the capability of the camera body is the limiting factor in that scenario, and the Panasonic lens nimbly kept pace with the OM-D's autofocus. Conversely, the lens' built-in OIS allows for hand-holding at extremely slow shutter speeds, and (look away now, Olympus fanboys) surpasses even Olympus' own excellent in-body image-stabilisation system.
Also welcome are the well-damped manual focus and zoom rings. The focus ring is not physically coupled to the lens elements; like most MFT lenses, it has focus by wire, where the focus collar rotation electronically sharpens the image in the EVF/rear screen. This can often be frustrating for MFT users who prefer manual focus. Happily, the responsiveness — both tactile and electronic — is smooth and accurate, making for a more enjoyable and precise manual focus experience. The only thing missing for purists like myself is a depth-of-field scale (remember them?).
So, how does the lens perform? Brilliantly. JPEGs and RAWs alike exhibit razor sharpness, extensive detail, inherent (ie, non-software) saturation and micro-contrast that put the lens on par with APS-C and full-frame equivalents of this focal length. It's incredibly well corrected, from wide open at 12mm to stopped down at 35mm, and performance is astonishingly even. It's a lens that can be used with confidence in every setting. Rare, indeed!
In short, Panasonic's Lumix 12-35 f/2.8 ASPH zoom is a fantastic lens that will separate hobbyists from serious shooters. The former won't be able to justify the cost on par with offerings from the bigger boys. The latter will find that in this focal length range, no other lens available right now will capture every pixel of their vision as well as this one does. If you're an MFT diehard fan, find the cash.