Sony DSC-W30 Optics

Zoom
A typical 3x optical zoom range, with good performance.

The Sony Cyber-shot DSC-W30 zooms over the equivalent of a 38-114mm range, which is fairly typical for its class. Overall performance is quite good, with good detail and sharpness at wide angle. The 2x Precision Digital zoom takes it out to 6x total, with the typical loss of resolution associated with Digital Zoom, although the W30 arguably does a better than average job.

Macro
A very small macro area, but severe blurring in the corners. Closest focusing distance is too close for the flash.

The Sony Cyber-shot DSC-W30's macro setting captures a very tiny minimum area of only 1.06 x 0.80 inches (27 x 20 millimeters). While the macro area is quite small though, details are somewhat soft throughout the frame, with sharp definition only in the very center of the frame. Most cameras have some softening in the corners in macro mode (evidence of the optical characteristic "curvature of field"), but the W30's blurring extends quite far into the frame. Sometimes, severe curvature of field of this sort is evidence of the camera being asked to focus closer than its minimum focusing distance, but a series of shots with the W30 at progressively greater focal distances showed the same phenomena.

The W30's flash had trouble throttling down for the macro area and was partially blocked as well, resulting in a very uneven exposure. (Plan on using external lighting for any macro shots with the DSC-W30.)

Distortion
Lower than average barrel distortion, slightly high pincushion.

This is the tendency for the lens to bend straight lines outward (like a barrel--usually at wide angle) or inward (like a pincushion--usually at telephoto). The DSC-W30's 0.5% barrel distortion at wide angle is less than average among the cameras we've tested, and not terribly obvious in most images. At the telephoto end, the DSC-W30's 0.4% pincushion is higher than average though.

Chromatic aberration
Moderate at wide angle (but small effect on images at edges, none at telephoto.

Chromatic aberration is low to moderate at wide angle, showing about 5-6 pixels of faint coloration on either side of the target lines, but decreases to very low levels at telephoto focal lengths. (This distortion is visible as a very slight colored fringe around the objects at the edges of the field of view on the resolution target.)

Corner Sharpness
Some softening in the left and right corners of the frame, strongest effect in the lower left corners. Better corner sharpness than average though.

The DSC-W30 produced soft corners in a few shots, the lower left corner seeming to have the most visible effect. Overall though, the W30's corner sharpness was better than that of most cameras we test.

Coverage
Optical viewfinder is tight and skewed to the top. Excellent accuracy from the LCD monitor.

The DSC-W30's optical viewfinder was quite tight, showing only about 81% frame accuracy at both wide angle and telephoto lens settings. However, the LCD monitor showed almost 100% accuracy at both wide and telephoto.