Panasonic DMC-ZS7 Optics

Zoom
A 12x optical zoom range, starting at a wide 25mm equivalent, with good performance. Average results from the 4x digital zoom.

The Panasonic ZS7's lens offers a very useful 12x optical zoom range, equivalent to a 25-300mm zoom on a 35mm camera. Performance at full wide-angle is quite good for such a wide-angle on a compact long-zoom, though detail is a hint soft across the frame with mild blurring in the corners. Chromatic aberration is visible along the edges, but well controlled for its class. At full telephoto, sharpness is very good across the frame, but chromatic aberration is more noticeable, especially in the tree branches. Results from the camera's 4x digital zoom are about average, with the typical loss in fine detail and artifacts you'd expect with 4x digital enlargement.

Macro
Smaller than average macro area, with strong detail in the center. The Panasonic ZS7's flash throttled down well, but was blocked by the lens.

The Panasonic ZS7's macro setting captured a fairly small minimum area measuring 1.66 x 1.25 inches (42 x 32 millimeters). Resolution and detail are excellent in the center, but corners were pretty soft, and the softness extends fairly far into the frame. (Most cameras have some softening in the corners in macro mode.) There is also some noticeable chromatic aberration in the dollar bill. The Lumix ZS7's flash did a pretty good job throttling down, but is blocked by the lens, casting a large shadow across almost have the image. You'll want to use external lighting for your closest macro shots. The ZS7 also offers digital enlargement during Macro, making for a tiny capture area, but detail isn't as good because of the interpolation.

Geometric Distortion
Lower than average distortion at both wide-angle and telephoto.

At full wide-angle, the Panasonic ZS7's images show about 0.5% distortion, which is lower than average, especially for a 25mm wide long-zoom. At full telephoto, distortion is "moustache-shaped" with about 0.1 % maximum deflection, also lower than average. We're pretty sure distortion is being corrected during processing, as Panasonic has been doing that for quite a while now on other models. 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 and Corner Softness
Moderate C.A. at both wide-angle and telephoto. Slight to moderate softness in some corners of the frame.

Chromatic Aberration. The Panasonic ZS7's 12x zoom lens exhibits moderate chromatic aberration at both wide-angle and telephoto. It's a little brighter at full telephoto, so it's slightly more noticeable than at wide-angle. The effect extends fairly deep into the frame, but the width and intensity of the fringes reduce as you move toward the center, where it's very low. Chromatic aberration is a type of distortion visible as a slight colored fringe around the objects at the edges of the field of view on the resolution target.

Corner Softness. The Panasonic ZS7's lens produced some soft corners at full wide-angle, but the softness doesn't extend very far into the frame. The top corners were both softer than the bottom corners, while the center was sharp. At full telephoto, corners were only slightly soft. The center was fairly sharp, suffering from slightly lower contrast than at wide-angle. Overall, this is a good performance considering the compact size and range of the lens.

Coverage
Very good accuracy from the LCD monitor.

The Panasonic ZS7's LCD monitor showed 100% coverage accuracy at wide-angle, and about 99% and at full telephoto. We did notice a slight vertical and horizontal shift, but still a very good performance here.