The S3-IS should be flattered. From the quantity of mail on the subject, we wanted to know when we could actually test it.  This camera was obviously long awaited. Many had even held out on other products hoping that this new camera would be fast with natural colors and produce very little noise. In the end, the S3-IS did turn out to be very good.  It’s huge and heavy at 500 grams, but this robustness is appreciable as well as its finishing touches, large moveable LCD and the 12x optic zoom in video. It’s also quite fast (startup is faster than the Panasonic FZ7 and Sony DSC-H1), which isn’t always the case on these big products. Nevertheless, there was still something to be desired, because the S3-IS isn’t better than the S2-IS.

A bigger sensor but with smaller photosites

Canon even admitted that the S3-IS is simply a S2-IS with a new 6 mega pixel sensor instead of a 5 megapixel. The lens didn’t change nor the body, and it has the exact same dimensions at 113 x 78 x 76 mm. If you think that more pixels = more precision in some ways this is true. For example, in one of our test photos, there is fine writing on a light background. Undeniably, the S3-IS is a little more precise here than the S2-IS. However, in the same photo a little higher on the right, there is a poster with numerous fine details and similar colors.  Here, the S2-IS does better and there was no movement of the camera (a tripod was used) nor any error on our part.  We took this same shot twenty times to confirm this.  This was done at the lowest sensitivity in order to have the most detail and a minimum of noise, however, this is exactly the problem. 



The higher the sensitivity the more noise

On the S2-IS, the lowest sensitivity is 50 ISO, versus 80 ISO for the S3-IS. Canon must have made this concession to compensate for the decrease in size of its 6 million photosites on the sensor (these are the micro cells that transform light into images). This is related to the fact that the 6 mega pixel sensor has the same dimensions as the previous 5 mega pixel and so the photosites are more tightly packed together.  For this reason, they receive a little less light, you need to go up in sensitivity, and this results in more noise in photos.  We noted last February in testing the Panasonic DMC-FZ7 that the S2-IS did not have the least noise in its category.  Other more recent models starting with the FZ7 and also the Sony DSC-H1 have cleaner photos.  You can see this in the upper right hand area with many of colors in the enlargement (2nd Detail) as well as in the photo with flash.

In the end, the 6 megapixel sensor increases the precision of details as well as the ambient noise level.  This equals a simultaneous increase and decrease in the quality of photos and confirms what Canon told us.  They should cancel each other out, but there are a growing number of users that prefer a slightly less precise but cleaner image.  For them, the S3-IS may be a bit disappointing.

We thank the photographers Patrick IMBERT and Michel QUENNEVILLE for their contribution to this article.