In summary
The fast f/1.7 maximum aperture and associated depth-of-field control are the key features that will attract buyers of this lens since its modest wide-angle coverage is included in all popular kit lenses. Aside from that, the excellent build quality and well-designed external controls will be welcomed by serious photographers.
We see this lens as being popular among photo journalists and street photographers who use M4/3 equipment and work in poorly-lit situations. Both will benefit from its compact size and light weight. The relatively high price tag (particularly in Southern Hemisphere countries) will put it out of the reach of family photographers, who could also benefit from these characteristics.
Full review
Announced in March, Panasonic’s new Leica-branded DG Summilux 15mm f/1.7 ASPH. lens is the latest companion lens for its Lumix G cameras. Covering the same angle of view as a 30mm lens on 35mm cameras, it replicates a ‘classic’ wide-angle lens for that format. The fast maximum aperture provides scope for shooting with a shallow depth of field and selective focusing plus the ability to be used in low-light levels.
The Panasonic Lumix G Leica DG Summilux 15mm f/1.7 ASPH. lens, shown without the supplied lens hood. (Source: Panasonic.)
Designed for cameras with Micro Four Thirds sensors, this lens can also be used on Olympus camera bodies, where the in-body stabilisation system will provide an advantage. Olympus produces a similar prime lens, the Olympus M.Zuiko Digital 17mm f/1.8, which isn’t quite as wide and is marginally slower but is much the same size and weight.
Both lenses include a manual aperture ring, which was over-ridden by the rear control dial on the Olympus OM-D E-M5 we used for some of our shooting tests. The Panasonic GH4 supported manual aperture adjustment with the ring. Panasonic includes a lens hood, whereas Olympus doesn’t.
The optical design of the Leica DG Summilux 15mm f/1.7 consists of nine elements in seven groups, including three aspherical elements to reduce distortion and spherical aberration. A Nano Surface Coating has been applied to lens elements to suppress lens flare and ghosting. Autofocusing is internal and controlled by a stepping motor, which operates quickly, quietly and smoothly, making this lens ideal for shooting video movies.
Who’s it for?
The fast f/1.7 maximum aperture and associated depth-of-field control are the key features that will attract buyers of this lens since its modest wide-angle coverage is included in all popular kit lenses. Aside from that, the excellent build quality and well-designed external controls will be welcomed by serious photographers.
We see this lens as being popular among photo journalists and street photographers who use M4/3 equipment and work in poorly-lit situations. Both will benefit from its compact size and light weight. The relatively high price tag (particularly in Southern Hemisphere countries) will put it out of the reach of family photographers, who could also benefit from these characteristics.
Build and Ergonomics
As expected for a Leica-branded, lens, the Summilux 15mm f/1.7 is very well built, with the main barrel being made from metal and polycarbonate plastic used for the adjustable parts, end caps and lens hood. The chromed metal mounting plate adds to the quality impression.
The manual aperture ring is located approximately 7 mm behind the front of the lens, where it is easily found by feel, thanks to prominent raised ridges and gaps on either side. It turns through an angle of slightly more than 90 degrees and is marked with aperture settings at full-stop intervals in an un-ridged section at the top of the ring.
Unmarked click stops between adjacent aperture settings provide precise control over aperture settings at 1/3EV increments. An ‘A’ setting on the left hand end of the ring sets the lens for automatic aperture adjustment by the camera’s controls.
Behind the aperture ring is a manual focusing ring, which is roughly 20 mm wide and carries a finely-ridged grip band. This ring is well-damped and turns smoothly, making precise manual focusing easy. (All current M4/3 cameras include manual focusing aids.)
A dedicated MF/AF switch is located on the left hand side of the barrel between the focusing ring and the camera body. The closest focusing distance for the lens is 20 cm, which isn’t ideal for close-up shots.
The supplied lens hood is an interesting conical shape. To attach it you must first remove a ring on the front of the lens that provides an attachment for the standard lens cap. This reveals a bayonet mounting for the hood.
There’s no index mark on the hood so it can be tricky aligning it with the mounting on the front of the lens. The hood is supplied with a push-on rubber cap that clamps onto its inner surface.
No stabilisation is provided, a not uncommon feature with wide-angle lenses. However, it can be used with Panasonic’s GX7 or Olympus PEN and OM-D cameras, all of which offer in-body image stabilisation.
Performance
We carried out our Imatest tests on this lens with the Panasonic Lumix DMC-GH4 camera, which was released a month beforehand. Test shots were also taken with this camera as well as with the Olympus OM-D E-M5.
Wide-open the lens produced sharp images in the centre of the frame with only slight edge softening between f/1.7 and about f/3.2. Imatest showed the highest resolution came at f/4, although resolution was generally very good from about f/2 to f/5.6, after which diffraction took effect, as shown in the graph of out Imatest results below.
Lateral chromatic aberration was negligible in the middle of the aperture range but edged into the low band at the widest and smallest aperture settings. In the graph below the red line marks the border between ‘negligible’ and ‘low’ CA.
Since distortion and chromatic aberration are corrected when outputting JPEGs in Panasonic cameras, we had to resort to raw files to assess these characteristics for the lens. Both were relatively slight, although nonetheless detectable.
Autofocusing was fast and very quiet with both the Panasonic and Olympus bodies we used for test shots. The Olympus body provided adequate stabilisation and allowed shutter speeds as slow as 1/6 second to capture a high percentage of images with adequate sharpness. Similar results required shooting at 1/20 second with the Panasonic GH4.
It was difficult to force the review lens to flare when it was pointed towards a bright light source. Even when the sun was inside the frame there was no loss of contrast if it was obscured and only traces of artefacts otherwise.
With a minimum focusing distance of 20 cm, this lens isn’t suitable for macro work. But it can be used for shooting close-ups of larger flowers and insects. The wide maximum aperture and circular aperture created by the seven-bladed iris diaphragm produce attractive bokeh with very smooth blurring and no distracting tonal transitions.
SPECS
Picture angle: 72 degrees
Minimum aperture: f/16
Lens construction: 9 elements in 7 groups (including 3 aspherical lens elements)
Lens mounts: Micro Four Thirds
Diaphragm Blades: 7 (circular aperture)
Focus drive: Stepping motor
Stabilisation: No
Minimum focus: 20 cm
Maximum magnification: 0.1x
Filter size: 46 mm
Dimensions (Diameter x L): 57.5 x 36 mm
Weight: 115 grams
Supplied accessories: Lens hood, two front caps, one end cap, soft carrying pouch
TESTS
Based on JPEG files taken with the Panasonic Lumix DMC-GH4 camera body.
SAMPLES
Vignetting at f/1.7.
Rectilinear distortion.
f/1.7; 1/2000 second at ISO 100.
f/2.8; 1/1000 second at ISO 100.
f/5.6; 1/250 second at ISO 100.
f/8; 1/250 second at ISO 200.
f/11; 1/125 second at ISO 200.
f/16; 1/80 second at ISO 200.
Close-up; 1/640 second at f/2.2; ISO 100.
Bokeh at f/1.7; 1/5000 second at ISO100.
Flare; ISO 100, 1/640 second at f/1.8.
Camera shake with Olympus E-M5 body; 1/6 second at f/8; ISO 800.
Camera shake with Panasonic GH4 body; 1/20 second at f/8; ISO 800.
1/400 second at f/8; ISO 200.
1/80 second at f/11; ISO 100.
1/125 second at f/5.6; ISO 100.
1/800 second at f/4; ISO 100. (JPEG original.)
1/125 second at f/7.1; ISO 100.
1/320 second at f/2.5; ISO 100.
Rating
RRP: AU$799; US$599.99
- Build: 9.0
- Handling: 9.0
- Image quality: 9.0
- Versatility: 8.5
