The Canon A540's compact body has a solid feel, thanks to its rugged body and healthy heft. Measuring 3.56 x 2.52 x 1.70 inches (90 x 64 x 43 millimeters), the A540 fits generous shirt pockets and larger coat pockets, purses, and hip packs, making it a good travel companion. The A540 has good heft, weighing 9.0-ounces (256-grams), with batteries and memory card, but isn't at all uncomfortable to carry. The two-toned silver body is sleek and understated with a retro look that's sophisticated enough for any age group.
The A540's front panel features the telescoping 4x zoom lens, which extends an additional 1-1/8 inches when fully extended to telephoto range. Also on the front panel are the optical viewfinder window, small microphone, flash, and a light emitter that serves multiple purposes, including autofocus assist, red-eye reduction, and the self-timer countdown. On the lower right side of the lens (as viewed from the rear) is a small button that releases the ring around the lens barrel. Removing the ring allows you to attach a lens adapter for extended telephoto, wide angle, or macro capabilities. There's also a good-sized hand grip on the front panel, created by the battery compartment.
On the right side of the Canon A540 (as viewed from the rear) is only the eyelet for attaching the wrist strap.
On the opposite side of the Canon A540 is the connector compartment, covered by a flexible, rubbery plastic flap that snaps in and out of place. When opened, the flap remains connected to the camera body, and folds out of the way to accommodate cables. Inside the compartment are the DC In, Digital (USB), and A/V Out jacks.
The A540's top panel features a Mode dial with 11 shooting positions divided into three basic categories: Auto Exposure, Image Zone, and Creative Zone. The Shutter button is located diagonally in front of the Mode dial, with a Zoom lever surrounding it. A Power button is on the other side and in front of the Mode dial.
The rest of the exposure controls are located on the Canon A540's rear panel, along with the optical viewfinder and 2.5-inch LCD monitor. The eye-level optical viewfinder features two LED lamps that report camera status. A Mode switch in the top right corner puts the camera into Playback or Record modes. To the left of the Mode switch is the camera's speaker. Below the Mode switch is a four-way multi-controller that navigates settings menus, pressing up, down, left, and right. The top edge also controls Flash mode, while the bottom edge accesses Macro and Manual Focus modes. A Set button at the center of the multi-controller confirms menu changes. Above the controller are the Exposure Compensation/Erase and Print/Share buttons. Below the controller are the Display and Menu buttons.
The A540's bottom panel is reasonably flat, with a sliding door to access the battery compartment and a threaded plastic tripod mount off in the opposite corner. The battery door and tripod mount are far enough away from each other to make quick battery changes while working with a tripod. Inside the battery door are wells for two AA cells, a small slot for the tiny CR1220 battery that maintains the camera's clock settings when the main batteries are out, and the SD/MMC memory card compartment.
Shutter Button: Resting in the center of the Canon A540's Zoom lever, this button sets focus and exposure when halfway pressed, and fires the shutter when fully pressed.
Zoom Lever (see image above): Surrounding the Shutter button on the Canon A540's top panel, this lever controls the optical and digital zoom while in Record mode. In Playback mode (when not using the playback zoom), the wide setting displays a nine-image index display of all images on the memory card, and accesses a "Jump" function that lets you scroll through index display screens quickly. Alternatively, the magnify position enlarges the currently displayed image as much as 10x, so that you can check on fine details.
Mode Dial: Also on the camera's top panel, this large, notched dial is used to select the camera's shooting modes. Canon divides these functions into three categories: Auto, Image Zone, and Creative Zone. The options are as follows:
Auto: The camera controls everything about the exposure, except for Flash and Macro modes, image size, and quality settings.
- Creative Zone
Program AE (P): Places the camera in control of shutter speed and lens aperture, while you maintain control over everything else (i.e., white balance, ISO, metering, exposure compensation, flash, etc.).
Shutter-Speed Priority AE (Tv): Allows you to control the shutter speed settings from 1/2,000 to 15 seconds, while the camera controls the aperture. All other exposure settings are available.
Aperture Priority AE (Av): Allows you to set the Canon A540's lens aperture from f/2.6 to f/8.0, while the camera controls the shutter speed. The maximum aperture depends on the zoom setting, ranging from f/2.8 at the wide angle end to f/5.5 at the telephoto position. In this mode, you maintain control over all other exposure variables.
Manual (M): Provides complete control over all the Canon A540's exposure settings, including shutter speed and lens aperture. As with aperture-priority mode, the maximum aperture varies with the zoom setting from f/2.6 at wide angle to f/5.5 at telephoto. The fastest shutter speed varies with the aperture and zoom setting:
- 1/1,250 at f/2.6-4.0 (wide) or f/5.5-7.1 (tele)
- 1/2,000 at f/4.0-8/0 (wide) or 8.0 (tele)
- Image Zone
Portrait: Uses a large aperture setting to blur the background while keeping the primary subject in sharp focus.
Landscape: Employs a small aperture setting to keep both the background and foreground in focus. (May use a slower shutter speed, so a tripod is recommended.)
Night Scene: Uses slower shutter speeds and flash to even out nighttime exposures. The slow shutter speed allows more ambient light to be recorded in the low-light areas, while the flash freezes the subject. The Red-Eye Reduction mode can be used with this exposure mode to eliminate Red-Eye in night portraits.
Scene: Accesses more specific preset shooting modes, including Night Snapshot, Kids & Pets, Indoor, Foliage, Snow, Beach, Fireworks, and Underwater. Also available are Color Accent and Color Swap.
Stitch-Assist: Allows you to record a series of images, either horizontally or vertically, to be "stitched" together into one large image or panorama on a computer.
Movie: Records up to 640x480-pixel 30-fps moving images with sound while space remains on the storage card.
Power Button: To the left of the Mode dial, this button turns the camera on or off.
Mode Switch: In the top right corner on the rear panel, this switch selects between Record and Playback modes.
Multi-Controller Rocker Button: The Canon A540's four-way rocker button isn't marked with arrows, but actuates left, right, up, and down, simulating arrow keys to navigate through settings menus. In Record mode, the left and right buttons adjust available exposure settings, as well as manual focus, when enabled. The top button controls flash mode, while the bottom button accesses Macro and Manual Focus modes.
In Playback mode, the left and right buttons scroll through captured images. When an image has been enlarged, all four arrows pan within the view.
Function Set Button (see image above): In the center of the multi-controller, this button confirms menu selections. It switches between available exposure adjustments in Manual mode. It also displays the following Function menu while in Record mode:
- ISO Speed: Sets the camera's sensitivity to Auto (except in Manual), or to 80, 100, 200, 400, or 800 ISO equivalents.
- White Balance: Controls the color balance of images. Options are Auto, Daylight, Cloudy, Tungsten, Fluorescent, Fluorescent H, Underwater, and Custom (manual setting).
- Drive Mode: Accesses Continuous Shooting and High Speed Continuous Shooting modes, and the three Self-Timer modes (a two- or 10-second delay, or the adjustable timer).
- Photo Effect: Enables Vivid Color, Neutral Color, Sepia, Positive Film, Lighter Skin Tone, Darker Skin Tone, or Custom Color picture effects.
- Flash Output: Adjusts the overall flash intensity from -2 to +2 EV in one-third step increments. In Manual mode, the flash fires only a single pulse, handy when you want to use the A540 with conventional "slave" triggers for external flash units.
- Light Metering System: Sets the metering mode to Evaluative, Center-Weighted, or Spot.
- Resolution & Quality: Specifies the image resolution and quality settings. Still image resolutions are 2,816 x 2,112; 2,272 x 1,704; 1,600 x 1,200; and 640 x 480 pixels. Wide Screen mode captures 2,816 x 1,584. Movie resolutions are 640x 480, or 320 x 240 pixels at either 30-fps or 15-fps. Quality options, available after pressing the Menu button, are Superfine, Fine, and Normal.
Exposure Compensation/Erase Button: Directly above left of the Canon A540's controller, this button increases or decreases the exposure from -2 to +2 exposure equivalents (EV) in one-third-step increments in Record mode. Not available in Manual mode, since the user controls the exposure variables directly there, but it is the button you use to switch between adjusting shutter speed and aperture. In Playback mode, it displays the single-image erase menu.
Print/Share Button: To the right of the Canon A540's Exposure Compensation/Erase button, is the Print/Share button. When connected to a printer or Windows computer, this button lights up, indicating that sync or printing is one button away.
Display Button: Below left of the multi-controller and adjacent to the lower right corner of the LCD monitor, this button controls the information and image display modes in Record and Playback modes.
Menu Button: Left of the Canon A540's Exposure Compensation/Erase button, this button calls up the settings menu in Record and Playback modes. It also dismisses the menu screen and backs out of menu selections.
Battery Compartment Latch: Nestled in the center of the battery compartment door on the bottom of the camera, this sliding switch unlocks the door, so that it can slide forward and open.
Lens Ring Release Button: Tucked under the lens on the camera's front panel, this button releases the lens ring. Once unlocked, the lens ring can then be turned and removed to accommodate accessory lens kits.