Panasonic GF3 Optics

Prime Lens
Very good performance with the 14mm f/2.5 kit lens.

The above shots were taken with the Lumix G 14mm f/2.5 ASPH Micro Four Thirds pancake lens. The 35mm equivalent focal length is about 28mm, a result of the GF3's 2x "crop factor." Results were excellent at f/8, with very good sharpness and contrast across much of the frame, and low levels of chromatic aberration and coma distortion in the corners. We can't really comment on corner sharpness because of the proximity of the trees in this shot, though, so we've added a Multi Target shot at f/8 below.

Since this is wide-angle lens with no optical zoom, we've also included shots with 2x and 4x digital zoom. They show pretty good results for digital zoom (particularly at 2x), though there's no getting away from the loss of detail associated with interpolation. The digital zoom shots also show that exposure can be different (underexposed in this case) compared to just cropping a full resolution shot after the fact, so that's something to be aware of.

Macro
A much larger than average minimum area, with very good detail. Flash had trouble though.

The Panasonic Lumix DMC-GF3's macro performance will depend entirely on the lens in use. However, with the 14mm kit lens, the Panasonic GF3 captured a much larger than average minimum area measuring 5.78 x 4.33 inches (147 x 110 millimeters). Detail was very good across much of the frame at f/5.6, though there's some moderate blurring in the corners which is not unusual. (Most lenses have some softening in the corners at macro distances.) The popup flash had trouble throttling down at such a close distance, resulting in a strongly overexposed image with uneven coverage. (Thus, external lighting may be the best bet for macro shots with this lens.)

Geometric Distortion
Low geometric distortion with the 14mm kit lens in JPEGs, much higher than average distortion in uncorrected RAW files.

When shooting JPEGs, the Panasonic GF3's 14mm kit lens produced just over 0.4 percent barrel distortion, which is much less than average especially for a wide-angle lens, and hardly noticeable in its images. 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 a RAW file from the above shot with dcraw, which does not correct for distortion. As you can see, the actual barrel distortion is very high at about 2.3%. 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 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 14mm kit lens in JPEGs. Uncorrected RAW files show much higher amounts. Corners were soft wide-open, but sharpen-up when the lens is stopped-down.

Chromatic Aberration. Chromatic aberration in the corners with the Panasonic Lumix DMC-GF3's 14mm kit lens is low to moderate in terms of pixel count in JPEGs, being somewhat exacerbated by the blurring, but coloration is fairly dull and bluish. The camera's processor does a pretty good job of reducing CA in JPEGs (see below for uncorrected RAW). As usual, color fringing gradually reduces in brightness and width as it approaches the center of the image, where it is almost non-existent.

Corner Softness. The Panasonic GF3's 14mm kit lens produced mild to moderate blurring in the corners wide-open at f/2.5, with the bottom right corner being the softest, though softness doesn't extend very far into the frame. Some corner shading ("vignetting") is also noticeable from the difference in brightness of the center versus corner crops above, especially wide-open. When stopped-down to f/8, corners become sharper, though still slightly soft, while the center remains very sharp. Vignetting also reduces when the lens is stopped-down, as expected.

Chromatic Aberration Correction. As mentioned above, the Panasonic GF3 applies chromatic aberration correction to its JPEGs, as uncorrected RAW files show much more distinct green and magenta coloration. RAW files converted with the bundled SilkyPix software are automatically corrected for CA and geometric distortion, so we used dcraw for the uncorrected conversions above right.

Shading Compensation
The Panasonic GF3 features optional Shading Compensation to reduce vignetting in JPEG images.

As you can see, the Panasonic GF3's Shading Compensation feature reduces corner shading quite effectively with the 14mm kit lens. Shading Compensation is off by default, not available when shooting video, and is not available with all lenses. Mouse over the links above to compare thumbnails, and click on the links to load the full resolution images.


Overall, a very good performance for a wide-angle pancake kit lens, and better performance than the typical zoom kit lens.

Accuracy
Excellent coverage accuracy from the LCD monitor.

The Panasonic GF3's LCD monitor proved quite accurate when used as a viewfinder, showing about 100% coverage with our low-distortion Olympus 50mm f/2 reference lens. Excellent results here.