Pentax Optio W60

Our lab testing of the W60 was a decidedly mixed bag. Low light performance wasn’t great, and our timing results were a problem for a camera destined for active lifestyle grab-shots. The camera turned in very good resolution scores, though, and the manual noise results were also impressive. As for the noise results when shooting in auto ISO mode, the W60 earned a digital dunce cap on that particular test.

Color (7.62)
There’s a reason that color performance is presented first among our battery of in-depth tests: when it comes to measuring technical camera performance, this is the one area that triggers a powerful emotional response. The impact of a brilliant blue sky, the warm reds and oranges of a fireplace, the blonde curls of a child all pop out for us as soon as we look at an image, long before you notice peculiarities in resolution or dynamic range. And while image editing software is frequently used to enhance color for dramatic effect, what we’re testing for here is accuracy. Mess with the reality of a photo for artistic reasons to your heart’s content, but we want to start out with a photo that faithfully captures the scene we saw.
Our color testing procedure calls for shooting a standard Gretag Macbeth color chart under controlled lighting conditions, at a variety of exposure settings. The resulting images are processed through Imatest image analysis software, which identifies off hues far more accurately than the human eye. For each color square in the Imatest chart below, the outer rectangle represents the color captured by the W60, the inner square is the captured color corrected for luminance, and the inset rectangle is the original chart color.

A second Imatest chart makes it easy to see the degree to which color reproduction accuracy suffers. In this chart, the ideal color is shown within the squares, the captured colors appear in the circles, and the length of the lines linking them indicates how the camera fared: shorter lines mean greater color accuracy.

In this representation of color performance,
shorter lines indicate greater accuracy.

When compared to four other cameras we’ve tested recently, the W60 is a significant notch below some of the dry-land competition, but substantially outperforms the Olympus Stylus 1030SW, it’s waterproof rival.

Resolution (8.16)
The number of megapixels a camera’s image sensor boasts doesn’t relate directly to the ability to create tack-sharp photos. Many camera systems, including optics, digital signal processing and image compression, combine to determine the final image quality. That’s why we shoot an industry-standard resolution chart with each camera, use Imatest to determine how precisely the actual photo produced by the camera captures the fine lines on the chart (scored as line widths per pixel  height, or lw/ph), and from that data produce a score which lets us compare performance across camera brands, models and specs.

A close-up of the industry-standard resolution chart we use for testing

The Pentax did well in our resolution testing, with a maximum performance of 1780 lw/ph with minimal oversharpening. This result was achieved at the lens’ widest zoom setting. Moving the camera back and shooting at higher telephoto magnification did cut resolution performance noticeably. While even at maximum zoom the resolution performance is acceptable, the camera clearly favors wide-angle, scenic shooting.

White Balance (7.89)
Inexpensive cameras have a tough time with this one – for that matter, quite a few pricey SLRs stumble when it comes to white balance testing as well. The challenge is adjusting to the different colors of light produced by varied sources of illumination. Sunshine, for example, isn’t white – it’s warm and reddish, where fluorescent light has a green tint. When we look at a white piece of paper under these very different sources of illumination, tough, our brains compensate. Cameras try to compensate, too, with three features. The easiest to use is choosing the Automatic setting, where the camera meters the light and adjust white balance accordingly. The second is selecting from a set of presets, built into the camera, which are  tailored to specific lighting conditions. Finally you can take a manual white balance reading by shooting a neutral white or gray surface under current lighting conditions.

We test the first two, shooting a color chart under varied light sources, including flash, fluorescent, shaded daylight and tungsten (incandescent), using both the automatic white balance capability and the white balance presets.

Auto White Balance (6.86)
The automatic white balance system didn’t cope well at all with tungsten illumination, the kind you’d find in a household with standard incandescent bulbs – this is always a problem area, but the W60 was particularly far off, and fluorescent light was another major problem. On the plus side, flash and shaded daylight photos were quite accurate in auto mode. In the following graphic representation of Imatest results, the difference between the original and the captured colors are exaggerated – you wouldn’t see this great a difference in your actual photos.

Preset (8.91)
Using the fluorescent and tungsten presets produced tremendous improvements in white balance accuracy. This is not always the case – just because a camera offers white balance presets doesn’t mean they’ll actually help performance under test conditions. In many cases, we’ve found presets that worked less well than the automatic system. Happily, the few seconds spent by the user invoking the W60 presets is time well spent. One minor caveat: the W60 doesn’t include a flash preset, found on most cameras, but the flash results in auto mode were fine in the first place.
 

Exaggerated White Balance Errors (Presets)

Florescent Preset WB - Fluorescent Illumination

Cloudy Daylight preset WB - Daylight illumination

Tungsten preset WB - Tungsten illumination

Averaging the automatic and preset scores produces a decent white balance score for the W60. Keep in mind, though, that a quick settings adjustment to the fluorescent and tungsten presets will deliver notably superior results.