Remember the days when digital cameras looked like digital cameras, instead of slivers of sculpted metal or retro SLRs?
Picking up the chunky A640 is like travelling back to a simpler era - it's unashamedly heavy, has an optical viewfinder and uses good old AA batteries. And while the PowerShot's charcoal grey casing might not be much to look at, it's made (mostly) from good old-fashioned metal and is home to that rarity: a fully-folding LCD.
The A640 isn't a camera designed to slip inside a pocket or to give to an eager child. But that doesn't mean it's tricky to use. The main control dial on top gives access to full PASM exposure modes, plus key scene modes and smooth (30fps) VGA movie capture. A four-way pad navigates the menus, and there are a couple of dedicated buttons for exposure compensation, display and menu access.
Of course, the A640 uses Canon's established Func button to alter key settings, such as ISO, white balance and the My Colours menu in a flash. More complex options, such as Flexi-zone autofocus and, surprisingly, slow sync or red-eye flash, are activated by plodding through the menus.
Sensitivity tops out at 'just' ISO 800, but this is no great sacrifice when you're working with a potentially noisy 10MP sensor. In use, the A640 is responsive and helpful. Like many compacts, it's nippiest when left in Burst mode: a respectable if not class-leading 1.5fps, with no limit on frames shot.
The 4x zoom isn't completely silent and takes a moment or two to shift focus points when zooming. In Macro mode, 1cm focusing is easily achieved, and reveals just how little distortion there is in the Canon optics. Manual focusing has a good interface, but there are just too few pixels on the LCD screen to check that your images are sharp, even with the central area thoughtfully magnified.
As batteries and screens have improved, digital cameras have evolved away from optical viewfinders, but they still have their uses - crucially, in very dark conditions or when power is fading.
So although the A640's small finder is predictably inaccurate, offering about 75% coverage, it's welcome nevertheless. The 2.5-inch vari-angle display is functional without being flashy. Detail and colour are accurately depicted, the viewing angle is generous and it performs well in low light.
The right-hand grip (whose smooth surface you might want to tape up for added grip) stores four AA cells. Use decent rechargeables and this can be a better solution than a customised lithium-ion battery, especially when you're stuck on holiday or away from a power socket.
A paltry 32MB SD card is supplied, and Super-fine JPEGs (no RAW capture) weigh in at around 5MB each. Performance is what you'd expect from a serious Canon: fast, reliable and generally accurate. Having said that, the nine-point AiAF occasionally selects the wrong subject in a scene.
Optically, there's just a smear of softness at full wide angle. Telephoto shots are sharp, contrasty and offer a decent maximum aperture (f/4.1) for portraits. Noise is very well controlled, with maximum ISO 800 shots maintaining colours and definition amid some grumbling chroma noise.
Colours are soberly reproduced, to the point that even the Vivid setting provides more realistic tones than you'll get from over-enthusiastic Kodaks and Fujifilms. Exposure is generally excellent, especially outdoors, where the Canon handles complex lighting admirably.
Images have vitality and crispness that's rare to find in today's over-cooked 10MP compacts. Fads come and go - this month, it's ultra- high sensitivity and face-detecting autofocus - but the PowerShot is built to last.
The A640 may not look sexy or have the fanciest interface, but it delivers where it counts: taking great-looking, high-resolution images at decent speeds and with minimum fuss. Mark Harris