Canon S3 IS Exposure

Exposure and White Balance

Indoors, incandescent lighting
Warm cast with Auto, but excellent color with both Incandescent and Manual white balance settings. About average exposure compensation required.

Color balance indoors under incandescent lighting was a little warm and reddish in Auto white balance mode, but excellent with both the Incandescent and Manual settings on the Canon PowerShot S3 IS. (Perhaps a bit greenish with the Manual setting, just a tad reddish with the Incandescent, but either call is really splitting hairs.) Even the results with Auto selected might be acceptable for some users. The Canon S3 IS required a +1.0 EV exposure compensation boost to get a good exposure, about average for this shot. The blue flowers somewhat dark and purplish here, but less so than with many cameras we test. (This is a very common outcome for this shot.) Our test lighting for this shot is a mixture of 60 and 100 watt household incandescent bulb, a pretty yellow light source, but a very common one in typical home settings here in the US.

Outdoors, daylight
Good color balance overall, with fairly bright colors. High contrast under bright outdoor conditions, but better than average preservation of highlight detail.

Outdoor shots showed better than average exposure accuracy, though with high contrast under harsh sunlight. The Canon PowerShot S3 IS does offer a contrast adjustment though, and setting it to the lower end of its range (as in the shot of Marti above) helps a fair bit in preserving highlight and shadow detail. Overall color looked pretty good, with bright reds and blues that nonetheless didn't look too overdone.

See full set of test images with explanations
See thumbnails of all test and gallery images

Resolution

High resolution, 1,250 lines of strong detail.

Our laboratory resolution chart revealed sharp, distinct line patterns down to about 1,250 lines per picture height, with extinction at around 1,700. (The camera produced slight color artifacts at lower line frequencies though, visible in the full-sized res target shots.) Use these numbers to compare with other cameras of similar resolution, or use them to see just what higher resolution can mean in terms of potential detail. Beware that while you might be able to make out what looks like distinct lines at numbers higher than those we've mentioned here, the camera is just doing its best to continue interpreting the lines. If you zoom in and follow them from the wider portions, you'll see the lines converge and reappear several times, so the lines you see at 1,600 and higher are really only artifacts generated by the camera's imaging system.

See full set of test images with explanations
See thumbnails of all test and gallery images

Sharpness & Detail

Sharp images, with some edge enhancement in areas of high contrast. Good shadow detail with low noise suppression.

The Canon S3 IS's images preserve high contrast detail like the fine branches against the sky above, with little or no evidence of oversharpening. (Edge enhancement creates the illusion of sharpness by enhancing colors and tones right at the edge of a rapid transition in color or tone.)

Noise-suppression systems in digital cameras tend to flatten-out detail in areas of subtle contrast. The effects can often be seen in shots of human hair, where the individual strands are lost and an almost "watercolor" look appears. The crop above right shows only slight evidence of this, with even darker areas of Marti's hair showing some detail. On balance, the Canon PowerShot S3 IS showed less detail loss due to noise reduction than do most cameras we test.

ISO & Noise Performance

Low noise at the normal sensitivity settings, but higher noise and some loss of detail at the higher settings.

The Canon S3 IS's lower ISO settings produced low to moderate noise, with only slightly blurred detail in the dark areas. (As noted above, better than average in this respect.) Starting at ISO 400, image noise becomes noticeable on screen, but we found ISO 400 shots surprisingly acceptable when printed at 8x10 inches. At ISO 800, noise becomes strong and blurring significant, but the images remain printable, certainly usable at print sizes of 5x7 inches and smaller.

Extremes: Sunlit and low light tests

High resolution with good overall detail, but high contrast limits both highlight and shadow detail somewhat. (Probably better than average though, when using the camera's contrast adjustment.) Very good low-light capability, sensitive enough to capture bright images under typical city street lighting and much darker conditions.

Sunlight:
Because digital cameras are more like slide film than negative film (in that they tend to have a more limited tonal range), we test them in the harshest situations to see how they handle scenes with bright highlights and dark shadows, as well as what kind of sensitivity they have in low light. The shot above is designed to mimic the very harsh, contrasty effect of direct noonday sunlight, a very tough challenge for most digital cameras. (You can read details of this test here.)

The Canon PowerShot S3 IS had some difficulty with the deliberately harsh lighting in the test above, producing high contrast with limited highlight detail, although the camera's contrast adjustment helped a fair bit relative to the unadjusted tone curve. Shadow detail is fairly good, but noise suppression takes its toll on detail in the deepest shadow areas. The Canon S3 IS required a slightly less than average amount of positive compensation at +0.7 EV, making its metering a bit more accurate than most in this particular test. (In "real life" though, be sure to use fill flash in situations like the one shown above; it's better to shoot in the shade when possible.)

Low light:
The Canon S3 IS had excellent low-light shooting capabilities, with a maximum exposure time of 15 seconds. The camera is sensitive enough for shooting under average city street-lighting at night, about one foot-candle, even at ISO 80 (the leftmost column of images in the table above). Overall color was pretty good with the Auto white balance setting, and the camera's autofocus system was able to focus on the subject down to the 1/4 foot-candle light level (about 1/4 as bright as typical street lighting) even without it's AF-assist light enabled. With the AF assist lamp active, the camera focused accurately down to the lowest light level we test at.

Coverage and Range

Somewhat uneven flash exposure at wide angle, excellent at telephoto. Good flash range.

Flash coverage was a bit uneven at wide angle, but much less so at telephoto. In the Indoor test, the Canon PowerShot S3 IS's flash underexposed our subject at its default setting, requiring a flash exposure compensation of +1.3 EV to get reasonably bright results. Even here, the exposure is a little dim, with a noticeable orange cast. The Slow-Sync flash mode also needed about +1.3 EV, though it produced more even lighting (and a stronger orange cast).

With a fixed ISO setting of 100, the flash was able to illuminate the DaveBox target adequately from six feet out to 15 feet at both wide angle and telephoto focal lengths, although the tele shots all seemed a little dim, regardless of distance.

Our standard test method for flash range uses a fixed setting of ISO 100, to provide a fair basis of comparison between cameras. We've now also begun shooting two shots using the manufacturer-specified camera settings, at the range the company claims for the camera, to assess the validity of the specific claims. In the shots above, the Canon PowerShot S3 IS seems to perform exactly as Canon says it will, producing good exposures at the rated distances with its ISO set to Auto. (Although as above, the telephoto shots turned out a little dim, regardless of distance.) The good news here is that the camera doesn't seem to be significantly boosting its ISO to achieve these excellent flash ranges. (The flash shots with auto ISO do have somewhat elevated noise levels, but not to the extent that we'd normally expect if a camera were boosting its ISO significantly in an attempt to achieve greater flash ranges.)

Print Quality

Very good print quality, great color, crisp prints at 8x10 inches, usable ones at 13x19. ISO 400 images are a bit soft but very usable at 8x10 inches. ISO 800 shots are usable at 5x7 inches, just fine at 4x6.

Testing hundreds of digital cameras, we've found that you can only tell just so much about a camera's image quality by viewing its images on-screen. Ultimately, there's no substitute for printing a lot of images and examining them closely. For this reason, we now routinely print sample images from the cameras we test on our Canon i9900 studio printer, and on the Canon iP5000 here in the office. (See the Canon i9900 review for details on that model.)

The Canon S3 IS produced crisp prints at 8x10 inches, and somewhat softer but still acceptable ones at 13x19. As usual, the real test of print size came at the higher ISO settings, but even there the S3 IS did very well. The Canon PowerShot S3 IS's ISO 400 images were a little soft and noisy when printed at 8x10 inches, but entirely acceptable for wall or table display. Even ISO 800 shots may be acceptable to some users when printed at 8x10 inches, but should be acceptable to most users when printed at 5x7 inches. All things considered, the Canon S3 IS does as well at ISO 800 as many competing models do at ISO 400.

Color-wise, the Canon S3 IS did very well indeed, with bright but very natural-looking color and good-looking skin tones.