The smallest and lightest full-range f/2.8 telephoto zoom lens with dust- and splash-proof construction for M4/3 cameras.
Panasonic announced its Lumix G X VARIO 35-100mm f/2.8 / POWER O.I.S. lens in mid-September 2012 as a ‘companion’ to the Lumix G X Vario 12-35mm f/2.8 ASPH lens, which was released earlier in the year. Like the 12-35mm lens, it is splash- and dust-resistant. Together, these two lenses make up the ‘prestige’ lens kit for the GH3 (and other G-Micro series) cameras. Covering a focal length range equivalent to 70-200mm in 35mm format, this lens is ideal for portraiture, sports and wildlife photography.
The optical design features 18 elements in 13 groups and includes one UED (Ultra Extra-Low Dispersion) element and two ED (Extra-Low Dispersion) lenses to minimise chromatic aberration and distortion. Panasonic’s Nano Surface Coating technology is applied to optical surfaces to minimise internal reflections across the visible spectrum, reducing the incidence of flare and ghosting.
Like the 12-35mm lens we have also reviewed (INSERT LINK), the 35-100mm lens uses internal focusing, which is driven by a stepping motor to ensure focusing is smooth and silent for both stills and movie capture. On the GH3 body we used for our tests, Panasonic’s Contrast AF system delivered fast and accurate autofocusing in a wide variety of shooting conditions.
POWER O.I.S. stabilisation provides roughly three f-stops of shake compensation for both low-frequency vibrations generated when the shutter button is pressed and large, slow movements when using slow shutter speeds. Seven blades close to a rounded aperture to ensure attractive bokeh.
Build and Ergonomics
Like the 12-35mm lens, the 35-100mm lens has a metal mounting plate with a thin rubber sealing ring to exclude dust and moisture. The rear section of its barrel is made from metal, as is the focusing ring, which has a 10 mm wide, finely-ridged grip band and is located 6 mm back from the front of the lens.
Focusing is totally internal, using the same kind of ‘focus-by-wire’ system as found in the 12-35mm lens. The focusing ring can be turned smoothly through a full circle manual if over-ride of autofocusing is needed.
The zoom ring is 45 mm wide and located a few millimetres behind the focusing ring. It carries a 37 mm wide ridged rubber grip band. Focal length settings for 35mm, 50mm, 70mm and 100mm are stamped just inside its leading edge in an arc of approximately 60 degrees. Stops at each end of the arc limit the ring’s rotation.
Unlike the 12-35mm lens, zooming is totally internal, which means the lens doesn’t extend as you move between the 35mm and 100mm positions. However, there’s no distance scale to show where the focus is set; only the same POWER O.I.S. on/off slider as is found on the 12-35mm lens.
According to the supplied instruction manual, the 35-100mm should be supplied with front and end caps, a cylindrical lens hood (which can be reversed for storage) and a soft storage pouch. Unfortunately, no lens hood was provided with the review lens.
This judgment was confirmed by our Imatest tests, which showed the review lens to be capable of meeting expectations for the GH3’s sensor at all focal length settings.
The highest figures recorded for centre resolution occurred with the 70mm focal length at f/5, although resolution was acceptably high from f/2.8 through to about f/6.3, where diffraction began to take effect. Slight softening could be seen in the extreme corners of frames and, to a lesser degree, near frame edges. The graph below shows the results of our Imatest tests.
Lateral chromatic aberration was negligible across all focal length and aperture settings, as shown in the graph of our Imatest results below. The red line indicates the point of transition between ‘negligible’ and ‘low’ CA.
Panasonic cameras apply corrections automatically to JPEG files, so this is to be expected, whereas Olympus cameras don’t. Test shots taken with our OM-D E-M5 body showed slight coloured fringing, which was most noticeable with the 35mm focal length.
Distortion is also corrected in Panasonic cameras, so it wasn’t surprising to find little evidence of distortion in test shots. Correction for vignetting is optional and accessed via the shooting menu. We found slight vignetting at the 35mm and 100mm focal lengths with f/2.8 but no noticeable corner darkening at the other focal lengths. Stopping down to f/3.5 eliminated it where it occurred.
Even without a lens hood, our test shots showed little loss of contrast and few artefacts when shots were taken in strong backlighting. Traces of veiling flare were seen in some strongly backlit shots at longer focal lengths, although they weren’t strong enough to compromise picture quality.
The M4/3 format reduces the background blurring potential by approximately two f-stops, compared with a 35mm camera. However, the wide f/2.8 maximum aperture produced attractive bokeh in close-ups with the longer focal lengths. Subject isolation was easy to achieve with wide aperture settings and blurred backgrounds tended to be more attractive with this lens than with the 12-35mm lens.
The POWER O.I.S. stabilisation was very efficient and enabled us to hand-hold the camera and lens with shutter speeds as slow as 1/8 second at around 85mm and achieve acceptable sharpness for about a quarter of the shots taken. At 1/15 second, more than half of the shots were reproduced sharply.
Fast and accurate autofocusing combined with the f/2.8 maximum aperture and the sophisticated stabilisation system make this lens an excellent partner for the GH3, particularly for photographers interested in low light shooting.
Like the 12-35mm lens, its high price tag (particularly for Australian buyers) causes us to have some reservations about recommending it, particularly for photographers who plan to fit this lens to an Olympus E-M5 body. Olympus includes sensor-shift stabilisation in its camera bodies, which makes in-lens stabilisation redundant. In fact, if you fit a stabilised lens to an Olympus camera you have to turn off the in-camera stabilisation system.
If you really need the f/2.8 aperture across the 35-100mm focal length range, this lens is the only option. But, if you can tolerate a slightly slower lens, Olympus offers a 40-150mm M.Zuiko Digital lens with f/4-5.6 maximum aperture for AU$349 (RRP). Its build quality and performance can’t match for the Panasonic lens. But we found it to be a good performer for its price when we reviewed it in May 2008.
Panasonic also has a cheaper alternative, the Lumix G Vario HD 45-175mm, f/4.0-5.6 ASPH./POWER O.I.S. which we reviewed in June 2009. The current RRP for this lens is AU$549.
Additional image samples can be found with our review of the Panasonic DMC-GH3 camera.
Not so good for:
RRP: AU$1699; US$1499.99