Canon A570 IS Exposure

Saturation & Hue Accuracy
Overall very good color, with good hue accuracy. Some slight oversaturation in reds, blues, and greens, but still quite good results.

Most consumer digital cameras produce color that's more highly saturated (more intense) than found in the original subjects. This is simply because most people like their color a bit brighter than life. The Canon PowerShot A570 IS does oversaturate strong red tones, and some blues and greens a little, but the results are still quite pleasing, rarely appearing overdone or unnatural.

Where oversaturation is most problematic is on Caucasian skin tones, as it's very easy for these "memory colors" to be seen as too bright, too pink, too yellow, etc. Here, the A570 IS did render skin tones slightly on the warm side in most cases, but many users find slightly warm skin tones more pleasing than cooler ones.

The other important part of color rendition is hue accuracy. Hue is "what color" the color is. Here, the A570 IS again performed well, though it pushed cyan tones toward blue (a common occurrence among many digital cameras, apparently a tactic aimed at producing pleasing sky colors), and some reds toward orange. Still, very good results.

Exposure and White Balance

Indoors, incandescent lighting
Good color with the Incandescent and Manual white balance settings, just a hint warm. Average positive exposure compensation required.

Color balance indoors under incandescent lighting was somewhat warm with the Auto white balance setting, both the Manual and Incandescent options produced much more accurate results. While the Incandescent setting held a bit of the warm cast of the original lighting, I chose the slightly more neutral (and more natural-looking to my eyes) Manual setting. The Canon A570 IS required an average amount of positive exposure compensation here, at +1.0 EV. Despite the slight warm cast, overall color with the Manual white balance setting is excellent, without the strong purple tints in the blue flowers we often see here. (Many digital cameras reproduce these flowers with a dark, purplish tint, so the A570 IS did very well here.) Our test lighting for this shot is a mixture of 60 and 100 watt household incandescent bulbs, a pretty yellow light source, but a very common one in typical home settings here in the U.S.

Outdoors, daylight
Good color and exposure, though slightly high contrast with the default settings.

Outdoors, the Canon PowerShot A570 IS performed pretty well, with only slight overexposure in the outdoor wide shot. The camera required no positive exposure compensation on the portrait shot, an unusual occurrence. Default contrast is on the high side, though the camera's contrast adjustment did a pretty good job of taming the exposure without weakening the color in the process. (See the version of the portrait shot with the A570's lowest contrast setting.) The A570 IS captured good color outdoors, without too much of a warm cast. Overall, pretty good results here.

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Resolution
High resolution, 1,500 ~ 1,600 lines of strong detail.

Our laboratory resolution chart revealed sharp, distinct line patterns down to about 1,500 lines per picture height horizontally, and about 1,600 lines vertically. Extinction didn't really occur horizontally, though lines began to merge around 1,900-2,000 vertically. 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.

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

Sharpness & Detail
Sharp images overall, very slight edge-enhancement artifacts on high-contrast subjects. Moderate noise suppression limits detail in the shadows.

The Canon PowerShot A570 IS captures sharp images with good detail definition, though some minor edge enhancement artifacts are visible on high-contrast subjects such as the crop above left. (Edge enhancement creates the illusion of sharpness by enhancing colors and tones right at the edge of a rapid transition in color or tone. In extreme cases, it produces "halos" around high-contrast edges.)

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 this, as the darker areas of Marti's hair show limited detail.

ISO & Noise Performance
Low to moderate noise at the normal sensitivity settings, but a big jump in noise with strong blurring at the higher settings.

Noise levels are low to moderate at the Canon A570 IS's lower sensitivity settings, with much higher noise at ISO 400 and higher (as you'd expect). Yellow/blue blotches are noticeable at the higher settings, which throws off the color balance a bit, and the camera's attempts at noise suppression eliminate some of the finer details. Still, it's not bad, retaining a surprising amount of detail up to ISO 800. (Even ISO 1600 shots are usable for 4x6 inch prints, if you don't mind some visible noise and lower color saturation.)

Extremes: Sunlit and low light tests
High resolution with strong overall detail, but slightly high contrast and limited shadow detail. Excellent low-light performance, capable of capturing bright images in near darkness, but focus can be problematic.

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 A570 IS produced fairly high contrast with deep shadows under the harsh lighting of the test above. However, the camera's contrast adjustment handled this problem fairly well, without strongly affecting color balance or tonal gradations. Detail is limited in the shadow areas, with some noise suppression visible. (See the version of the portrait shot with the A570's lowest contrast setting.) Though some areas look a little dark at the default exposure, I preferred it to the image at +0.3 EV, which had too many blown highlights for my preference. (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 PowerShot A570 IS captured bright images down to the 1/16 foot-candle light level (about 1/16 as bright as average city street lighting at night). At ISO 80, the image at this lowest light level is a bit dim, but really still usable. The camera's autofocus system was able to focus on the subject down to just below the 1/4 foot-candle light level without the AF assist light, so you'll need to make sure it's enabled for darker conditions. (Even though the camera indicated that it was focusing in the shots above with the AF assist light though, many of the shots here appear to be slightly out of focus.) Do keep in mind though, that the very long shutter times necessary here absolutely demand the use of a tripod or other camera support to get sharp photos. (A useful trick is to just prop the camera on a convenient surface, and use its self-timer to release the shutter. This avoids any jiggling from your finger pressing the shutter button, and can work quite well when you don't have a tripod handy.)

NOTE: This low light test is conducted with a stationary subject, and the camera mounted on a sturdy tripod. Most digital cameras will fail miserably when faced with a moving subject in dim lighting. (For example, a child's ballet recital or a holiday pageant in a gymnasium.) For such applications, you may have better luck with a digital SLR camera, but even there, you'll likely need to set the focus manually. For information and reviews on digital SLRs, refer to our SLR review index page.

Coverage and Range
Slightly dim exposures at the default flash exposure setting, but the camera required less-than-average exposure compensation for flash exposures. Typical range.

Flash coverage was uneven at wide angle; and though it was more even at telephoto, the range and exposure decreased due to the lens' much smaller aperture there. Indoors, under incandescent background lighting, the Canon A570 IS's flash underexposed our subject a little at its default setting, requiring a +0.7 EV exposure compensation adjustment to get bright results. The camera's Slow-Sync flash mode (here, using Night Scene mode) coverage is more even, though with a noticeable orange cast.

At wide angle, shots at ISO 100 are bright out to a distance of about 11 feet, decreasing in brightness from that point on. At full telephoto and ISO 100, even the 6-foot shot is a little dim, and the images darken from there. A typical result for compact models.

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 A570 IS seems to perform exactly as Canon says it will, producing good exposures at the rated distances with its ISO set to Auto.

Print Quality
Good print quality, very good color, nice-looking 13x19 inch prints, very sharp 8x10s. ISO 400 images are soft but usable at 8x10, ISO 800 shots are good to 5x7, ISO 1600 ones to 4x6 inches.

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 iP5200 here in the office. (See the Canon i9900 review for details on that model.)

The Canon PowerShot A570 IS had enough resolution to make very nice-looking 13x19 inch prints, and very crisp 8x10s. Its ISO 400 images were a little soft but usable for making 8x10 inch prints. As you go to higher ISO settings, the images soften quite a bit: ISO 800 images are OK at 5x7 inches, ISO 1600 shots are really only usable at 4x6 inches, and do still show some noise at that size. Still, we think most consumers would find 4x6 prints from ISO 1600 acceptable, certainly better than not getting the shot at all, or getting one that was too blurred to be usable. Overall, a nice performance from an affordable camera.