The A540 is a more full-featured, less compact alternative to the spritely PowerShot SD600, though its position in the A series between the very similar 5-megapixel A530 and the 6-megapixel A700 seems to exist solely to fill the price gap between the two.
At 3.6 by 2.5 by 1.7 inches and 7.8 ounces when loaded with an SD memory card and a pair of AA batteries, this camera feels relatively lightweight and fits comfortably in your hand. You zoom via a jog dial that's concentric with the shutter button. Rotating the dial is easier when shooting with two hands; still, one-handed shooting is entirely practical. The coarse, 85,000-pixel, 2.5-inch LCD tends to wash completely out in direct sunlight, but you can always use the bright optical viewfinder instead.
Canon's usual A-series mode dial sits atop the camera and, like the conveniently arranged array of buttons on the camera back, can be operated with your right thumb. Together, these controls make the A540 responsive and easy to navigate. For example, you can spin the mode dial to switch between auto, programmed, manual, aperture priority, or shutter priority, plus scene modes including Portrait, Landscape, Night Scene, Stitch Assist, and Movie. Another 10 scene modes are available at the SCN notch on the dial. Beginners and less experienced shooters will likely opt for program autoexposure, switch to full auto, or choose one of the scene modes.
Metering options include evaluative, center-weighted, or spot. When in a shooting mode other than auto, manual, or movie, the trash/EV button adjusts exposure to plus or minus 2EV in 1/3EV increments. It's accompanied by a print-sharing button and a Disp key that varies the amount of information displayed on the LCD. Up and down keys toggle flash and macro focus modes, respectively. Other setup and shooting functions are logically divided among menus accessed through the menu and function/set buttons.
Intermediate and advanced shooters will love Canon's user-friendly exposure controls. Left/right cursor keys let you make shutter- and aperture-priority adjustments. In full manual mode, the EV button toggles between shutter speed (15 seconds to 1/2,000 second) and f-stop (f/2.6 to f/8) control. The 35mm-to-140mm (35mm-camera equivalent) zoom lens focuses to as close as 2 inches using lamp-assisted and one- or nine-point autofocus or manual focus. Finally, you can shoot movies at a maximum of 640x480 pixels at 30fps.
In line with the A540's enthusiast fan base, this camera supports add-on lenses that affix to a bayonet mount under the plastic collar around the lens. Current options include 1.75X telephoto and 0.75X wide-angle lenses, as well as any 52mm filter adapter. For those who live the life aquatic, there's also an underwater case. Though this camera lacks a hotshoe, you can attach a higher-powered HF-DC1 accessory flash. It fits on a bracket that screws into the tripod socket and fires as a slave in cordless mode.
There are a number of cool features, such as Color Swap mode, which lets you photograph, say, purple roses by exchanging all the reds in a scene with an alternate color, as well as a 4.4-megapixel wide-screen framing mode. The ISO 800 sensitivity setting also comes in handy and isn't quite as noisy as those we've seen on some compact cameras.
Low shutter lag and robust continuous shooting are the biggest strengths of the Canon A540. Under high-contrast lighting conditions, this camera's autofocus system lets it snap off a picture in 0.7 second and lags about 1.1 seconds under more challenging low-contrast light, even with the crimson focus-assist lamp. The camera responds quickly to fast-moving shooting situations, powering up for an initial shot in 1.9 seconds, with shot-to-shot times of just 2 seconds thereafter. However, when using the slow-charging built-in flash (effective for even coverage out to about 11 feet at ISO 800), between-shot pauses extended to 4 seconds during testing and almost 6 seconds in practice. (Flash-recycle time varies with battery type and capacity.) The red-eye-prevention mode only partially tamed red pupils in our test subjects. The A540 maintained a steady 2.3fps in continuous-shooting mode, regardless of resolution and with seemingly no limit to the number of shots.
We like this camera's photos, which are quite good for its class. The exposure system tends to favor shadows at the expense of highlights; dark areas have lots of detail, while bright areas wash out. We found less chromatic aberration than we expected with purple fringing around backlit subjects surprisingly absent. Flesh tones were often warm, but other colors were fairly accurate, if muted. Flash exposures tend to be a little warm, and automatic white balance sometimes produces reddish casts under incandescent light. As you might hope, noise levels were low at the minimum ISO 80 sensitivity setting and rose significantly at ISO 400, but the images were still tolerable when we boosted ISO to the maximum ISO 800.
The Canon PowerShot A540's image quality and full manual controls will no doubt appeal to advanced photographers looking for a backup to their dSLRs. At the same time, beginners will like the many scene modes and its full auto mode too. Of course, if 4X zoom isn't enough for you, there's always the near-identically featured A700 for just a little extra cash.
(Shorter bars indicate better performance)
|Typical shot-to-shot time||Time to first shot||Shutter lag (typical)|
(Longer bars indicate better performance)
|Typical continuous-shooting speed|