Canon SX1 IS Optics

Zoom
An impressive 20x optical zoom lens with good overall performance. Average results from the 4x digital zoom.

The Canon SX1 IS's optical zoom offers an impressive 20x optical zoom range, equivalent to a 28-560mm zoom on a 35mm camera. Performance at full wide angle is pretty good for such a long zoom, with only minor blurring and coma distortion in the corners. It does still fall prey to long-zoom trade-offs, though, with moderate to strong chromatic aberration along the edges of the frame, as well as a small amount of flare. At full telephoto, detail is also very good throughout the frame, with only a small amount of blurring in the corners. There's still a fair bit of chromatic aberration at maximum zoom, bit it isn't quite as visible with this subject as it is wide angle. The camera's 4x digital zoom performs about average, with the typical loss in fine detail and artifacts associated with digital enlargement.

Macro
A small macro area, with very good detail near the center. The SX1IS's flash did a good job up close.

The Canon SX1 IS's macro setting captured a very small minimum area measuring just 1.49 x 1.12 inches (38 x 29 millimeters) using standard macro mode. Resolution and detail are excellent near the center, but corner softness extends fairly deep into the frame. (Most cameras have some softening in the corners in macro mode.) Surprisingly for such a large lens, the Canon SX1 IS's flash did a good job of throttling down for the macro area and getting the light in underneath the lens, resulting in a more even exposure than without the flash. Oddly, we were not able to focus any closer in Super Macro than in normal Macro mode.

Geometric Distortion
Higher than average barrel distortion at wide-angle, but virtually no pincushion at telephoto.

The Canon SX1 IS's 0.9% barrel distortion at wide-angle is slightly higher than average compared to the most consumer digital cameras, though not surprising for a 20x wide-angle zoom. At the telephoto end, the SX1 IS's less than 0.1% (about 0.03%) pincushion distortion is extremely low; essentially imperceptible. Distortion 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).

Chromatic Aberration
High and bright distortion at wide-angle and telephoto.

Chromatic aberration is high at wide-angle, showing about 6-8 pixels of bright coloration on either side of the target lines. At telephoto, the amount and brightness of the chromatic aberration similar, though the color has shifted from purple-green to blue-yellow. Chromatic aberration is a form of distortion visible as a slight colored fringe around the objects at the edges of the field of view on the resolution target.

Corner Sharpness
Minor blurring in the corners of the frame at wide-angle, stronger blurring at full telephoto.

The Canon SX1 IS produced slightly soft corners of the frame at wide-angle, with the top-left corner being the softest. At full telephoto, blurring was much stronger, with both left corners being softer than the right.

Coverage
Excellent accuracy from both the EVF and LCD monitor.

The Canon SX1 IS's electronic viewfinder and LCD monitor both showed essentially 100% coverage accuracy at wide-angle and at telephoto. Great results!