Panasonic G5 Optics

Zoom Lens
A typical zoom ratio for a kit lens, with fair performance.

The above shots were taken with the Lumix G X VARIO PZ 14-42mm f/3.5-5.6 Power O.I.S. zoom kit lens. The 35mm equivalent focal length is about 28-82mm which is typical for a kit lens. Results at full wide angle (18mm) are good at f/8, but detail is a touch soft across most of the frame, with hints of flare around bright objects. Extreme corners exhibit mild to moderate blurring and minor coma distortion. Chromatic aberration is well controlled at all focal lengths (the G5 suppresses C.A.). Performance at medium focal length (26mm) is fair, again with a hint of softness and flare, while corners are blurred. At full telephoto (42mm), the lens is softer across the frame, corners are softer still, and there is some noticeable vignetting (shading) in the corners as well. The Panasonic G5's digital zoom mode shows a typical loss of fine detail for such a high magnification, as well as more obvious chroma noise in the shadows.

Macro
A larger than average minimum area, with somewhat soft detail and strong corner shading. Flash throttled down well, though.

The Panasonic Lumix DMC-G5's macro performance will depend entirely on the lens in use. However, with the 14-42mm X kit lens, the Panasonic G5 captures a much larger than average minimum area measuring 3.77 x 2.83 inches (96 x 72 millimeters). Detail is a little soft across the frame at f/8, with additional softening in the corners. (Most lenses have some additional softening in the corners at macro distances.) There's also some fairly strong vignetting or corner shading in the extreme corners, much more than we're used to seeing especially stopped-down to f/8. The popup flash had no trouble throttling down at this distance, resulting in a pretty good exposure, though corner shading is still visible as expected (caused by the lens).

Geometric Distortion
Low geometric distortion with the 14-42mm X kit lens in JPEGs, though strong distortion in uncorrected raw files.

When shooting JPEGs, the Panasonic G5's 14-42mm kit lens produces about 0.4 percent barrel distortion at wide angle, which is much less than average and just slightly noticeable in its images. Pincushion distortion at full telephoto is less than 0.1 percent, also much lower-than-average and hardly noticeable. This is the tendency for the lens to bend straight lines outward (like a barrel -- usually at wide-angle).

To see how much correction is taking place in the camera, we converted raw files from the above shots with DxO Optics Pro with corrections disabled. As can be seen above, actual barrel distortion at wide angle is very high at about 2.1%, while pincushion at telephoto is fairly high, at about 0.7%. We expect this for smaller interchangeable lenses though, so it's nothing to be concerned about unless you are using a raw converter which does not understand the embedded "opcodes" to perform distortion corrections automatically. Most raw converters these days (including Adobe Camera Raw and SilkyPix) are capable of applying distortion correction automatically, as specified by the manufacturer. There is however going to be some loss of resolution in the corners as a result of such correction, because pixels in the corners of the frame are being "stretched" to correct for the distortion. Obviously, a lens that doesn't require such correction, and is also sharp in the corners to begin with would be preferable, but relaxing constraints on distortion brings other benefits in the lens design, such as a very compact design.

Chromatic Aberration and Corner Sharpness
Low to moderate levels of chromatic aberration from the kit lens in JPEGs. Uncorrected raw files show higher amounts. Corners are somewhat soft wide open, but improve when the lens is stopped down.

Chromatic Aberration. Chromatic aberration in the corners of JPEGs taken with the Panasonic G5's 14-42mm X kit lens is moderate at wide angle, but coloration is fairly dull and bluish. At full telephoto, C.A. is quite low in the corners. As usual, color fringing gradually reduces in brightness and width as it approaches the center of the image, where it's almost non-existent at both ends of the zoom range. Thus, the camera's processor does a pretty good job of reducing lateral C.A. in JPEGs (see below for uncorrected raw).

Corner Softness. The Panasonic G5's 14-42mm X kit lens produces minor to moderate blurring in all four corners at wide angle when wide open at f/3.5, while the center is fairly sharp. Corners have stronger blurring at full telephoto with the top corners a bit softer than the bottom, and the center is a bit soft as well.  

Vignetting. Moderate corner shading ("vignetting") is noticeable at both wide angle and telephoto, as can be seen from the difference in brightness of the center versus corner crops above. The G5 does offer shading compensation, though. See below.

Stopped down to f/8, corner sharpness improves, but they're still a touch soft. Center sharpness also improves slightly. Vignetting (corner shading) improves quite a bit to the point of being almost negligible.

Chromatic Aberration Suppression. As mentioned above, the Panasonic G5 suppresses chromatic aberration in its JPEGs, with uncorrected raw files showing more distinct magenta and green coloration along high-contrast edges. Raw files converted with the bundled SilkyPix software or Adobe Camera Raw are automatically corrected for C.A. and geometric distortion, so we used DxO Optics Pro with corrections disabled for the uncorrected conversions above right.

Overall, a fair performance for a kit lens. Performance isn't bad on lower-resolution bodies, but the 16-megapixel G5 is slightly more demanding of lenses, making this kit lens's optical flaws more noticeable.

Shading Compensation
The Panasonic G5 features optional Shading Compensation to reduce vignetting in JPEG images.

Mouse over the links above to compare thumbnails, and click on the links to load the full resolution images.

As you can see, the Panasonic G5's Shading Compensation reduces corner shading with the 14-42mm X kit lens, so it's a useful feature. Shading Compensation is off by default, not available when shooting video or when burst rate is set to SH, and is not available with all lenses. It may also produce more visible noise in the periphery, particularly at higher ISOs.

Accuracy
Very good coverage accuracy from the electronic viewfinder and LCD monitor.

The Panasonic G5's electronic viewfinder and LCD monitor both proved quite accurate in record mode, showing just over 100% coverage with our low-distortion Olympus 50mm f/2 reference lens. Very good results here.