Panasonic Lumix G 42.5mm f1.7 review

25th April 2015

Written by Gordon Laing

Quality

To evaluate the real-life performance of the Lumix 42.5mm f1.7 lens, I shot this exterior scene at every aperture setting using an Olympus OMD EM1 mounted on a tripod.

The EM1 was set to its base sensitivity of 200 ISO and the lens focused on the center of the composition using magnified Live View assistance. The corner and center crops shown below were taken from the areas marked with the red squares, right, and presented at 100%.

I also shot this scene moments later using the Olympus 45mm f1.8 lens for a direct comparison and you can find this lower on the page.

I shot the scene using the EM1’s RAW mode and processed the files in Adobe Camera RAW (ACR) via Photoshop using the following sharpening settings: 50 / 0.5 / 36 / 10. All lens corrections were disabled, so there’s no software compensation for vignetting, geometric distortion or chromatic aberrations, although note the camera may be applying some corrections before the RAW file is recorded which can’t be disabled.

The Lumix 42.5mm f1.7 delivers superb results across the frame, even wide-open at its maximum aperture of f1.7. It’s consistently crisp right into the corners, although you’ll enjoy a boost in sharpness and contrast across the frame if you close the aperture to f2.8. I’d say the optimal range of apertures are between f2.8 and f5.6, with diffraction starting to take its toll from f11 onwards. There’s little if anything to complain about here, but please do scroll down to see how it compares to the Olympus 45mm f1.8 lens, as you may be surprised. Alternatively skip to my Lumix 42.5mm sample images or head straight to my verdict.

Lumix 42.5mm f1.7 corner sharpness		Lumix 42.5mm f1.7 center sharpness

Lumix 42.5mm f1.7 corner crop at f1.7		Lumix 42.5mm f1.7 center crop at f1.7


Lumix 42.5mm f1.7 corner crop at f2		Lumix 42.5mm f1.7 center crop at f2


Lumix 42.5mm f1.7 corner crop at f2.8		Lumix 42.5mm f1.7 center crop at f2.8


Lumix 42.5mm f1.7 corner crop at f4		Lumix 42.5mm f1.7 center crop at f4


Lumix 42.5mm f1.7 corner crop at f5.6		Lumix 42.5mm f1.7 center crop at f5.6


Lumix 42.5mm f1.7 corner crop at f8		Lumix 42.5mm f1.7 center crop at f8


Lumix 42.5mm f1.7 corner crop at f11		Lumix 42.5mm f1.7 center crop at f11


Lumix 42.5mm f1.7 corner crop at f16		Lumix 42.5mm f1.7 center crop at f16


Lumix 42.5mm f1.7 corner crop at f22		Lumix 42.5mm f1.7 center crop at f22

Panasonic Lumix 42.5mm f1.7 vs Olympus 45mm f1.8

In the two tables below you’ll see how the Lumix 42.5mm f1.7 compares against the Olympus 45mm f1.8, first in the middle of the frame, then in the corner. Note due to its slightly longer focal length, the Olympus is delivering a slightly tighter field of view and therefore resolving slightly finer details. The thing to look for in the comparisons below are the overall sharpness and contrast.

Starting with the crops from the middle of the frame, I’d say both lenses are roughly similar in sharpness, although the Lumix 42.5mm starts with a little higher contrast. By f4 though, they’re fairly evenly matched in performance.

But scroll down to the corner crops and you’ll see a stark difference between them. While the Lumix manages to deliver a very crisp result in the far corner, even at its widest and aperture, the Olympus is much softer and doesn’t approach the same quality until it’s closed down to f5.6. Indeed the Olympus looks quite poor in this comparison, but this performance is not uncommon for most lenses, which are generally softer in the extreme corners at their wider apertures. It’s the Lumix here that’s performing above average.

At this point the members of some forums weigh-in and claim I have a poor copy of the Olympus lens. I’ve actually tested several copies of the Olympus 45mm f1.8 and all have performed similarly. I find it a great lens that’s sharp in the middle when wide-open, and sharp across most of the frame if you close it down to f4-5.6. It’s just that it’s being compared here against a lens that simply delivers better results in the corners at larger apertures. Remember your own results may vary depending on the subject and distance. I can only show you what I’ve found in my own tests, and as you’ll see on the main page of the review, there’s areas where the Olympus out-performs the Lumix. But in terms of contrast and sharpness across the frame on a distant subject, the Lumix 42.5mm is comfortably out-performing the Olympus 45mm, which is a great result for Panasonic.

Next skip to my Lumix 42.5mm sample images or head straight to my verdict.

Lumix 42.5mm f1.7 center sharpness		Zuiko Digital 45mm f1.8 center sharpness

Lumix 42.5mm f1.7 center crop at f1.7		Zuiko Digital 45mm f1.8 center crop at f1.8


Lumix 42.5mm f1.7 center crop at f2		Zuiko Digital 45mm f1.8 center crop at f2


Lumix 42.5mm f1.7 center crop at f2.8		Zuiko Digital 45mm f1.8 center crop at f2.8


Lumix 42.5mm f1.7 center crop at f4		Zuiko Digital 45mm f1.8 center crop at f4


Lumix 42.5mm f1.7 center crop at f5.6		Zuiko Digital 45mm f1.8 center crop at f5.6


Lumix 42.5mm f1.7 center crop at f8		Zuiko Digital 45mm f1.8 center crop at f8


Lumix 42.5mm f1.7 center crop at f11		Zuiko Digital 45mm f1.8 center crop at f11


Lumix 42.5mm f1.7 center crop at f16		Zuiko Digital 45mm f1.8 center crop at f16


Lumix 42.5mm f1.7 center crop at f22		Zuiko Digital 45mm f1.8 center crop at f22

Lumix 42.5mm f1.7 corner sharpness		Zuiko Digital 45mm f1.8 corner sharpness

Lumix 42.5mm f1.7 corner crop at f1.7		Zuiko Digital 45mm f1.8 corner crop at f1.8


Lumix 42.5mm f1.7 corner crop at f2		Zuiko Digital 45mm f1.8 corner crop at f2


Lumix 42.5mm f1.7 corner crop at f2.8		Zuiko Digital 45mm f1.8 corner crop at f2.8


Lumix 42.5mm f1.7 corner crop at f4		Zuiko Digital 45mm f1.8 corner crop at f4


Lumix 42.5mm f1.7 corner crop at f5.6		Zuiko Digital 45mm f1.8 corner crop at f5.6


Lumix 42.5mm f1.7 corner crop at f8		Zuiko Digital 45mm f1.8 corner crop at f8


Lumix 42.5mm f1.7 corner crop at f11		Zuiko Digital 45mm f1.8 corner crop at f11


Lumix 42.5mm f1.7 corner crop at f16		Zuiko Digital 45mm f1.8 corner crop at f16


Lumix 42.5mm f1.7 corner crop at f22		Zuiko Digital 45mm f1.8 corner crop at f22