Canon PowerShot S90

Resolution (12.97)

our test for the resolution of the images that the S90 captured, we found that it did an excellent job overall. Images were extremely sharp, and low distortion and only slight chromatic aberration. It is important to note here that we are testing the sharpness of the images, not the native resolution that the camera captures at. More on how we test resolution.

Distortion (7.93)

The S90 has a 5x zoom lens, and we found that this only adds a very small amount of distortion to the images it captures. At the wide and middle points of the zoom range, we did notice some slight distortion; around 1.3 per cent of barrel distortion at both ends. What this means is that straight edges (such as walls or lampposts) may look slightly bowed outwards at both ends of the zoom range. The distortion at the telephoto end of the zoom range was less than half a per cent, which is barely noticeable.

Distortion Examples
Wide (6.0mm): 1.4% Barrel Distortion
Mid (15.0mm): 1.3% Barrel Distortion
Tele (22.5mm): 0.46% Barrel Distortion

Sharpness (18.06)

We were extremely impressed with the sharpness of the images that the S90 shot; they were consistently sharp both across the frame and across the zoom range. There were a few minor issues, though; the edges of the frame at the zoom settings were slightly softer than the middle, particularly those on the left side of the image. However, even these edges were not a huge problem; fine details were still captured in the image, but without the razor-sharp clarity of the middle.You can see examples from our test images in the crops below.

Chromatic Aberration (7.82)

Chromatic Aberration occurs because the elements of the lens deflect colors of light differently; it usually shows up as a slight colored fringe to high contrast edges, such as the edges of the blocks in our color chart. We saw some evidence of this from the S90, particularly at the wider zoom settings. However, the amount of aberration that we saw was low, even at the wider zoom settings.

Quality & Size Options (5.83)

The S90 has a wide range of image size and quality settings, ranging from the maximum 10 megapixel images down to 0.3 megapixel images. In addition, there are two quality settings: fine and standard. The S90 is also unusual amongst point & shoots in being able to capture RAW images, which contain the raw data from the image sensor. The S90 can also capture a RAW and JPEG image simultaneously, giving the convenience of a JPEG and the quality of the RAW at once.

Image Stabilization (0.97)

The S90 includes an optical stabilization system that moves an element of the lens in response to camera shake, but we found that this was only moderately effective. We test this on point & shoot cameras by attaching the camera to our stabilization system, setting the camera to shoot at 1/30 of a second and taking photos with stabilization on and off. For the S90, we found that the images with stabilization on were slightly sharper than with stabilization off, but only by a very small amount. More on how we test image stabilization.

Stabilization Comparisons
Canon S90	Panasonic DMC-ZS3	Canon SD970 IS	Fujifilm F200EXR
Stabilization Off
Stabilization On