Canon A570 IS Optics

Zoom
Very good performance with the 4x optical zoom lens. Digital zoom also performs fairly well.

The Canon PowerShot A570 IS's optical zoom covers the equivalent of a 35-140mm range, which is slightly greater than most average digital cameras. Results were quite good at wide angle, with minimal blurring in the corners and low coma distortion in the tree branches against the sky. The camera's 4x digital zoom also performs pretty well, with tolerable losses in resolution and quality from the digital upsampling to full resolution.

Macro
A small macro area with excellent detail and high resolution. Flash exposure was not usable up close.

The Canon A570 IS's macro setting performed quite well, capturing a very small minimum area of 2.18 x 1.63 inches (55 x 42 millimeters). Detail and resolution were both excellent, though there's a moderate amount of softening in the extreme corners from the lens. (Most cameras have some softening in the corners in macro mode.) The flash blew out the exposure a fair bit, with a strong shadow in the lower right corner of the frame from the lens. Plan on using external lighting for the best results with the A570 IS's macro setting.

Distortion
Moderate barrel distortion, though low 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 Canon PowerShot A570 IS's 0.9% barrel distortion at wide angle is just a little more than average among the cameras we've tested, and quite noticeable in some of its images. (Particularly if you have straight lines near the edges of the frame.) At the telephoto end, the A570 IS's pincushion distortion was quite low at 0.1%, and had little effect.

Chromatic aberration
Moderate, only slightly noticeable effect on images at edges.

Chromatic aberration is moderately high at wide angle, showing about 5-6 pixels of bright coloration on either side of the target lines, but it extends only a little way into the frame. (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.) At telephoto, chromatic aberration is much lower. Overall, the effect was only slightly noticeable in most of our test shots.

Corner Sharpness
Slight blurring in the right corners of the frame at wide angle, less blurring at telephoto; good sharpness overall.

The Canon PowerShot A570 IS produced slightly soft corners in the right side of the frame at full wide angle, with minimal blurring on the left. At full telephoto, there's only slight blurring in the corners of the frame, with very little effect on resulting images. Overall sharpness was quite good.

Coverage
Very good accuracy from the LCD monitor, though the optical viewfinder proved a bit tight.

The Canon PowerShot A570 IS's optical viewfinder was a bit tight, showing approximately 80% coverage at wide angle, and 82% at telephoto. It was also tilted to the left somewhat. The camera's LCD monitor was essentially 100% accurate (to within the limits of our measurement) at both wide angle and telephoto.