The Panasonic Lumix G 25mm F1.7 ASPH is a compact and lightweight prime lens for Micro Four Thirds camera bodies. It offers an equivalent focal length of 50mm in full-frame terms, and an equivalent maximum aperture of F3.4. This lens is a great choice for general-purpose photography, including low-light work.

At $250 USD and available now, the Lumix G 25mm F1.7 is a solid option whether you’re looking for a companion to your ‘kit’ zoom lens or you just want something small and fast to shoot with.

Key specifications:

• Focal length: 25mm (50mm Full-Frame equivalent)
• Aperture range: F1.7 – 22
• Stabilization: None built-in
• Filter thread: 46mm
• Close focus: 0.25 m (9.84″)
• Maximum magnification: 0.14x
• Diaphragm blades: seven
• Hood: yes (plastic, included)
• Weight: 125 g (0.28 lb)
• Optical construction: 8 elements in 7 groups

ISO 200 | 1/800 sec | F4 | Panasonic Lumix DC-G9

Ah, the nifty fifty. Back in the film camera days, long before the advent of the zooming kit lens, camera companies often shipped their consumer and enthusiast bodies kitted with a 50mm lens; a practice I’d be thrilled to see come back. After all, they say you become a better photographer, faster, ‘zooming’ with your feet rather than zooming with your lens. Why? Because moving around forces creativity and often opens up new perspectives!

Anyhow, the hallmark of any good nifty fifty, then and now, is a favorable ratio of quality to price. And Panasonic’s modern take for Micro Four Thirds fits the bill nicely: though it’s very affordable, it’s capable of producing lovely images.

Follow along as we jump into handling, AF behavior, and optical characteristics to find out if this lens is also a good choice for you.

Sample images in this review were edited in Adobe Camera Raw with adjustments limited to white balance and exposure parameters. Sharpening and noise reduction were left at ACR defaults.

Handling

At 125g (4.4 oz) in weight and just 52mm (2 in) in length, this 25mm F1.7 is among Panasonic’s smallest and lightest prime lenses. The mount is metal while the body is constructed of plastic. Despite the delightfully lightweight design, it looks and feels well-built.

As one should expect at the price point, this 25mm offers a bare-bones feature-set. There’s no optical stabilization, though this shouldn’t matter for the vast majority of shooters, as almost all modern Micro Four Thirds bodies have internal IS. Nor is there an aperture ring or custom buttons. What the lens does offer is a sizable focus ring.

The front accepts 46mm filters and a plastic lens hood, H-H025, is included in the box. The hood attaches bayonet style, so it can be used with a filter. It can also be attached backward, to save space.

Compared to…

Olympus also makes a ‘nifty fifty’ similar to this one. It’s a little more expensive, but it’s also a bit more compact. Other options in this segment include the faster, though longer Sigma 30mm F1.4 and the higher-end Panasonic/Leica 25mm F1.4 II.

Here’s how they all stack up:

Autofocus and focus breathing

The Panasonic 25mm F1.7 is plenty fast to focus on a Lumix body; and shooting in AF-S tends to lead to faster AF acquisition than using AF-C. The lens is also snappy to focus with Olympus bodies, though given how close in price the Olympus 25mm F1.8 is to this lens, we’d recommend sticking with the native option for best AF performance.

The minimum focus distance of 0.25m or just shy of 10 inches is solid. Users will be able to get fairly up-close and personal with their subjects. And focusing is internal, meaning the lens does not increase in size as it racks.

For video shooters, focus breathing – where the framing shifts as the focus is pulled – is fairly well controlled. This is good news for folks who may want to manually rack focus for a cinematic effect. The manual focus action is a focus-by-wire affair and responsive enough; the ring itself turns with no hard stop at either end of the focus range.

The lens is also impressively quiet when using AF in video mode thanks to its stepper motor. We tested it with a Panasonic G9 and found the touchscreen makes it painless to move focus smoothly and silently, with just the tap of a finger.

Image quality

Sharpness

ISO 200 | 1/4000 sec | F1.7 | Panasonic Lumix G9

This Panasonic 25mm F1.7 is fairly sharp across the focal plane, wide open. And even on the highest resolution 20MP Four Thirds sensors, its resolving power should leave most users satisfied.

That being said, stopping down just a bit to F2 or F2.8 will result in the sharpest output. But sharpness will drop quite visibly by even F5.6 and certainly by F8, due to diffraction (remembering that F5.6 – F8 on Four Thirds is F11 – F22 in full-frame terms). So it’s better to crank your shutter speed in bright light, rather than go beyond those apertures, if possible.

Vignetting and distortion

This lens displays minimal vignetting wide open. And any noticeable vignetting is gone by F2.8. ISO 200 | 1/1250 sec | F2.8 | Panasonic Lumix G9

While the lens has a fair degree of barrel distortion in its optical design (which is to be expected, as the M43 system prioritizes compact size), distortion is fully corrected for, digitally, in the camera’s JPEGs and/or in your Raw converter. This means straight lines will look, well, straight (see the images above the flowers for an example). The lens also shows minimal vignetting wide open and any traces of vignetting are gone by F2.8.

If the tiny bit of vignetting does bother you, it can easily be corrected for in post. I personally enjoy it, though, as a matter of taste. But to each their own!

Bokeh

ISO 200 | 1/2000 sec | F1.7 | Panasonic Lumix G9

The bokeh – or quality of the out-of-focus regions produced by this 25mm – is fairly pleasing. Panasonic takes pride in the smoothness/polishing of its aspherical surfaces/molds, and it shows here. The discs rendered by out-of-focus highlights are relatively Gaussian and free of distracting patterns like ‘onion rings’. Only occasionally do they show the slightest hint of a hard edge (more noticeable as you stop down), but not enough to cause any concern.

At F1.7, bokeh near the edge of the frame displays a ‘cat eye’ effect.	At F4, bokeh looks much more uniform, in terms of its shape.

However, when shooting wide open, bokeh near the edge of the frame looks lopsided, displaying the classic ‘cat eye’ effect. While this can lead to a slightly less shallow DOF effect at edges, it’s perfectly acceptable for a lens of this type, and wasn’t severe enough to yield swirly bokeh in our shots. More importantly, the discs near the corners aren’t truncated in an odd or distracting manner.

The ‘cats-eye’ bokeh is mostly gone by F4. However, bokeh discs becomes less rounded. Specifically, the polygonal shape of the lens’s 7-blade aperture becomes more pronounced in the out-of-focus highlights, when you stop down past F2.8, and this can have a slightly negative impact on bokeh in general.

The Panasonic 25mm F1.7 is capable of producing images with good subject separation from the background. ISO 200 | 1/3200 sec | F2.2 | Panasonic Lumix G9

Flaring, ghosting, and sunstars

Lens flare can cause some loss of contrast especially when shooting directly into bright light sources, while multiple ghosts of bright sources can manifest themselves as colored ‘blobs’ that get more defined the more you stop the lens down. ISO 200 | 1/800 sec | F16 | Panasonic Lumix G9

Even when shooting with the included lens hood attached, artifacts from lens flare can be pretty distracting with this lens. You may notice ghosting when shooting directly into the sun, usually manifesting as a multiple-color haze or purple blobs.

When shooting bright light sources at stopped-down apertures – like in the F16 shot above – the ‘spikes’ of the sunstar are soft-edged and not all that well pronounced.

Lateral and longitudinal chromatic aberration (fringing)

The out-of-focus regions in this F1.7 shot show some purple fringing in front of the subject, aka longitudinal CA (LoCA) ISO 200 | 1/3200 sec | F1.7 | Panasonic Lumix G9

Lateral chromatic aberration – or purple/green fringing near the edge of the frame in high contrast regions – is very well controlled for optically, and is further corrected for digitally in JPEGs and/or in your Raw converter. Here are uncorrected and corrected Raw conversions – as you can see the differences are minor.

Longitudinal CA (LoCA) – or purple and green fringing manifesting in front of and behind the plane of focus – can be fairly noticeable wide open and is hard to manually correct for. That said, stopping down the lens just a bit helps to mitigate it, and although it doesn’t entirely disappear even by F2.8, it’s not too distracting either.

While the Panasonic 25mm F1.7 shows some longitudinal CA wide open, it becomes much less noticeable when you stop down a bit. Still, at 100%, you can certainly spot some purple and green fringing in the out-of-focus regions on the left side of this image, in the vines and stems. ISO 200 | 1/2000 sec | F2.8 | Pansonic Lumix G9

Conclusion

The Pansonic Lumix G 25mm F1.7 ASPH is an affordable and capable option for Four-Thirds shooters seeking something more versatile than the kit lens, especially for low-light photography. It’s well-built, compact, and fast/quiet to focus, making it a good choice for stills and video shooters alike.

Of course, for a little more money, you can get Sigma’s slightly faster 30mm F1.4 DC DN lens, which is also a strong optical performer. But the trade-off is a tighter crop (60mm in Full-frame terms) and a lens construction that’s quite a bit longer and about twice as heavy as the Panasonic.

ISO 200 | 1/800 sec | F5.6 | Panasonic Lumix G9

For folks desiring the absolute best 50mm equiv. output for Panasonic Micro Four Thirds cameras, the Panasonic Leica DG 25mm F1.4 II is the ticket. However, at nearly three times the cost of the Panasonic 25mm F1.7, it’s not the easiest lens to justify. It’s even harder to justify given how solidly this more affordable prime performs.

Ultimately, though it’s not optically perfect, for most folks, the Panasonic Lumix G 25mm F1.7 ASPH is going to be more than good enough.