Canon A580 Exposure

Saturation & Hue Accuracy
Very good overall color and hue accuracy, with minor oversaturation of some colors.

Saturation. The Canon PowerShot A580 oversaturates red, blue, and some green tones slightly, but overall saturation is just about right. Exaggerated reds and blues are typical of many consumer models, but the A580's color was pleasing on a wide range of typical subjects. 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.

Skin tones. Here, with the color balanced properly for the light source, the PowerShot A580's skin tones were slightly pinkish, but still good. 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.

Hue. The Canon PowerShot A580 showed only a few small color shifts relative to the correct mathematical translation of colors in its subjects. We noticed slight shifts in cyan toward blue, as well as a push of red toward orange, and some yellows toward green, though overall hue accuracy was very good. Hue is "what color" the color is.

Exposure and White Balance

Indoors, incandescent lighting
Slight warmth with Auto white balance. Incandescent and Manual options produced better, nearly identical results. Average positive exposure compensation required.

Color balance indoors under incandescent lighting was slightly warm in Auto white balance mode, while both the Incandescent and Manual settings more accurate results. Both Manual and Incandescent options were nearly identical, but the Manual option appeared best overall. The Canon PowerShot A580 required a +1.0 EV exposure compensation boost to get a good exposure, about average for this shot. Overall color with the Manual white balance setting is quite good, though there is the hint of a magenta tint and slightly pinkish skin tones. Also, the blue flowers are quite dark, and slightly purplish. (Many digital cameras reproduce these flowers with a dark, purplish tin.) 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
Slightly high contrast outdoors, but still good overall exposure and color.

Outdoors, the Canon PowerShot A580 performed fairly well, though contrast is a little high under the harsh lighting. On the portrait shot, highlights are very hot on the white shirt, and shadows quite deep. Shadow detail is fair in both shots, though details are fuzzy from noise artifacts as well as some blurring from noise suppression. Overall color is pretty good, however. For harsh lighting like this, consider using the A580's adjustable contrast setting to even out the exposure.

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Resolution
High resolution, 1,300 ~ 1,400 lines of strong detail.

Our laboratory resolution chart revealed sharp, distinct line patterns down to about 1,400 lines per picture height horizontally, and to about 1,300 lines vertically. Extinction didn't really occur, though lines began to merge around 1,900 lines. 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, with only minor edge-enhancement on high-contrast subjects. Noise suppression limits detail slightly in the shadows.

Sharpness. The Canon PowerShot A580 produced good, sharp details overall. Slight enhancement artifacts are visible on high-contrast subjects such as the crop above left, but results are still good. Edge enhancement creates the illusion of sharpness by enhancing colors and tones right at the edge of a rapid transition in color or tone.

Detail. The crop above right shows some noise suppression in the darker areas of Marti's hair, which limits detail definition of individual strands. There's also some chroma noise remaining in the shadows and blurry areas. 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.

ISO & Noise Performance
Low to moderate noise at the normal sensitivity settings, and good results at mid-level settings. A jump in noise with strong blurring at the highest settings.

The Canon PowerShot A580 produces low to moderate noise at its normal sensitivity settings of 80 and 100, with good results still at ISO 200. At ISO 400, noise is higher, as is noise suppressing blurring, but results are still pretty good overall. At the highest settings of 800 and 1,600, noise is much stronger, with strong losses in fine detail and a lot of chroma noise.

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

Sunlight. The Canon PowerShot A580 produced high contrast under the harsh lighting in the test shots above, with hot highlights on the white shirt and dark shadows. Shadow detail is limited, with blurred detail from noise artifacts as well as some noise suppression. The camera required about average compensation to get proper exposure of skin tones, at +0.7 EV, but unfortunately blows the detail in the shirt. The camera's lower contrast settings did a good job of producing a more even exposure, however, so definitely consider adjusting contrast in situations like the one above. You can also use the fill flash in situations like the one shown above; it's better to shoot in the shade when possible.

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.)

Low light. The Canon PowerShot A580 performed well on the low-light test, capturing bright images at the lowest light level down to the ISO 200 sensitivity level. At ISO 80, images were bright to about 1/8 foot-candle. Color balance was pretty good with the Auto white balance setting. The camera's autofocus system worked well also, as it was able to focus on the subject almost down to the 1/16 foot-candle light level unassisted, and beyond to the darkest light level with the AF assist enabled. (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.)

How bright is this? The one foot-candle light level that this test begins at roughly corresponds to the brightness of typical city street-lighting at night. Cameras performing well at that level should be able to snap good-looking photos of street-lit scenes.

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
A slightly dim flash even at close range. Our standard shots required slightly higher than average exposure compensation.

Coverage. Flash coverage was uneven at wide angle, with strong falloff in the corners and at the edges of the frame. At full telephoto, coverage was more uniform, but dim. In the Indoor test, the PowerShot A580's flash underexposed our subject at its default setting, requiring a +1.3 EV exposure compensation adjustment to get good results. The camera's Slow-Sync flash mode produced slightly brighter results, but with a stronger orange cast from the room lighting.

ISO 100 Range. At wide angle, flash shots at ISO 100 remained fairly bright out to a distance of about 10 feet, decreasing in brightness from that point on. At full telephoto and ISO 100, the target was bright to about 7 feet, with decreasing intensity from there.

Manufacturer Specified Flash Test. In the wide angle shot above, the PowerShot A580 performs close to Canon's claims, producing slight overexposure at the rated distance with its ISO set to Auto (which selected ISO 250). At telephoto, the camera again boosted ISO to compensate, though not as much. 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.

Print Quality
Good print quality, good color, sharp 11x14-inch prints. ISO 400 images are soft but usable at 8x10, ISO 800 shots are good at 5x7.

The Canon A580 had enough resolution to make good looking 11x14-inch prints, though with some minor chroma noise in the shadows, even at ISO 80. ISO 200 shots start to soften a bit at 11x14, but with more chroma noise. Color noise disappears at ISO 400, but quality drops, making 11x14-inch prints a little too soft; it's better at 8x10. ISO 800 shots are soft at 8x10, better at 5x7, though color has started to fade. ISO 1,600 shots are barely acceptable at 4x6 inches, so this setting is best avoided.

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.)