Very compact, the Lumix G 20mm f / 1.7 II Asph. is a prime objective for practicing street photography in all discretion. But it will be necessary to close the diaphragm to exploit its full potential.
This is not a novelty, far from it elsewhere since the Panasonic Lumix G 20mm f / 1.7 II Asph. was announced in 2013 and it was already a cosmetic update of the first edition. However, it never went through our test lab and you were many to claim it. A gap now filled.
Made from 7 optical elements divided into 5 groups, the lens incorporates two aspherical lenses. Designed to work with the Micro 4/3 hybrids, it offers a focal length of 20mm that covers a field equivalent to that of a 40 mm in 24x36. Its diaphragm is composed of seven lamellae and its maximum aperture extends to f / 1.7. It is devoid of optical stabilization, the function being entrusted to housings with internal mechanical systems. Its minimum focusing distance of 20 cm gives it a maximum magnification ratio of 0.13x (0.25x in 24x36 equivalent). But its main strength lies in its compactness and lightness since it measures only 63 mm in diameter for 26 mm long and weighs only 87 g.
- Focus at 20 cm.
- Opening f / 1.7.
- No distortion.
- No vignetting.
- No chromatic aberrations.
- Handy perfectible in manual focus.
- No seals.
- Diaphragm slats visible.
- Medium dive.
- Quality recessed at large openings.
Panasonic Lumix G 20mm f/1,7 II Asph review
The main advantage of this Lumix G 20mm f / 1.7 II Asph. is obviously its compactness. It is hardly beyond the handle of the GX8 that we used for our test, which makes it possible both to house it in any bag and to do the street photography in all discretion . But this compactness does not allow the lens to offer an aperture setting ring or autofocus mode selector. You have to go through the box to switch to manual focus. The absence of a stop at the ends of the focusing ring does not play in his favor and even if a scale of distances is displayed in the viewfinder, some users will regret that no marking is present on the lens. As for the ring itself, its friction seems well adapted, but it lacks a non-slip coating. The manufacture of the lens is however not up to the highest-end models since we have found no seal. Watch out for rainy weather!
Its field of coverage equivalent to that of a lens of 40 mm focal length in 24x36 gives this Lumix 20 mm f / 1.7 a great versatility. It can be used for both street and portrait photography or for close-up focusing with a minimum focus distance of 20 cm. Its use has been pleasant and its large f / 1.7 aperture makes it possible to play with shallow depths of field as to compensate for a weak light and the absence of integrated stabilization. Its bokeh, however, is not flawless and although Panasonic says it has a "circular" diaphragm, its polygonal shape is clearly visible in the background.
To enjoy a greater brightness, it will be necessary to consider turning to references like M.Zuiko Digital ED 25mm f / 1.2 PRO or Leica DG Summilux 25mm f / 1.4 Asph, with superior qualities, but at the price of a significant congestion and a much higher price. Side distortion, nothing wrong. The Lumix G 20mm f / 1.7 II Asph. can be used for architectural plans without a correction in post-production is essential. Ditto for vignetting, totally invisible even when fully open. As for autofocus, it is efficient and fast, but lacks discretion. The sound of the engine will not be heard in street photography, but could be embarrassing in show, for example, or during video recordings.
The measurements in our laboratory are made in partnership with Imatest. Software, tools or charters, Imatest offers complete and customized solutions to analyze and test the quality of cameras and photographic lenses. The concept of dive is quite delicate to treat. This can be likened to the "sharpness" or "precision" that is observed in an image. It can be very different from one lens to another, from one focal point to another and from one openness to another. It can also vary between the center and the edges of the image. We tested the lens with a Panasonic GX8 to the Micro 4/3 sensor of 20.3 Mpx and a definition of 5 184 x 3888 px. Each pixel thus measures 3.33 μm on one side.
The sharpness of the lens is quite low at full aperture. It is necessary to close the diaphragm starting from f / 2,8 to see the values to go up, although they remain rather average. The Olympus M. Zuiko Digital 25mm f / 1.8 does better, just like the M.Zuiko Digital 25mm f / 1.2 or the recent Lumix Leica DG Vario Summilux 10-25mm f / 1.7 ASPH. The homogeneity is not bad, without being exceptional, since the angles always remain in withdrawal. This trend is also highlighted on our test scene. At f / 1.7, no detail is transcribed with great clarity. The results are better from f / 2.8, but the edges of the image remain behind and it is necessary to close at f / 5,6 or even f / 8 so that the quality becomes visually more acceptable. The lens has no chromatic aberration.
There are few pancake lenses that offer excellent picture quality and this Panasonic Lumix G 20mm f / 1.7 II Asph. does not belong to it. It remains versatile, fun to use and has many advantages, such as the absence of vignetting and distortion, and an f / 1.7 aperture that allows working in low light or playing with shallow depths of field. Its extreme compactness and low price are its main assets and the reasons that lead us to designate it as an interesting model for entry-level Micro 4/3 hybrid users looking for a complement for their kit zoom .
Lumix G 20mm f/1,7 II Asph