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White Balance

The A700 has five white balance presets (daylight, cloudy, tungsten, fluorescent and fluorescent H) in addition to the default auto white balance. There is also a 'custom' white balance setting, which allows you to point the camera at a white or gray object and set the white balance manually. The custom white balance setting is remembered even if you turn the camera off. In normal outdoor shooting the auto white balance works perfectly (as confirmed by our studio tests). Indoors it's a bit more hit and miss, as we've seen with most Canon PowerShots, both fluorescent and incandescent (tungsten) lighting cause fairly strong color casts. Best to stick to the preset (or one-push custom WB) or the tungsten preset if you want more neutral colors.

Incandescent - Auto WB
Red 13.0%, Blue -19.9%
Poor
Incandescent - Incandescent preset WB
Red 4.3%, Blue 0.5%
Good
Fluorescent - Auto WB
Red 1.7%, Blue -14.1%
Average
Fluorescent - Fluorescent preset WB
Red -0.0%, Blue -1.2%
Excellent

Flash Performance

The A700's built-in flash has a quoted working range of 0.55m - 3.5m (1.8-11.0 ft) at the wide end of the zoom and 0.55m - 2.5m (1.8-8.2 ft.) at the tele end - which isn't great, but you're unlikely to be using flash at the long (210mm equiv.) end of the zoom that often. It also works down to about 30cm (12 inches) in macro mode (in all cases assuming the ISO is set to auto). In our real-world tests the flash did a perfectly good job within its effective range, exposing perfectly in a wide range of situations and with virtually no color cast. Recycle time can feel very slow, especially at the long end of the zoom or when the batteries are running low. In normal use the recycle time is 4-5 seconds, at worst it stretches to 7-10 seconds.

Skin tone
Excellent color, Slight underexposure
Color chart
No color cast, very slight underexposure

Macro Focus

As is common to most compact digital cameras the A700's macro mode is most effective at the wide end of the zoom, where you can get as close as 1cm - very impressive. The macro mode is only usable in the first half of the zoom range (up to about the 100mm equiv. point), but even at the long end of the zoom you can focus down to about 55cm, capturing an area just over 10cm across. There is inevitably some distortion when shooting very close up at the wide end, but it is not too strong, and certainly less so than many of its competitors. In both these shots you can see a little mild Chromatic Aberration (CA).

Wide macro - 20 x 15 mm coverage
138 px/mm (3510 px/in)
Distortion: Average
Corner softness: Average
Equiv. focal length: 35 mm
Tele macro - 103 x 77 mm coverage
27 px/mm (688 px/in)
Distortion: Very low
Corner softness: x
Equiv. focal length: 210 mm

Barrel and Pincushion Distortion

Barrel distortion is - at 1.1% - around the average for a camera in this class, and certainly doesn't mar real world scenic shots. There is a small (0.4%) amount of measurable pincushion distortion at the telephoto end of the zoom.

Barrel distortion - 1.1% at Wide angle
Equiv. focal length: 35 mm
Pincushion distortion - 0.4% at Telephoto
Equiv. focal length: 210 mm

Specific Image Quality Issues

No real complaints here - the A700 produces clean, sharp, detailed results in a wide variety of shooting situations. Colors are natural and white balance generally very accurate (unless you're shooting under artificial lighting), although there is a slight tendency to over saturate bright primary colors. We're not talking groundbreaking image quality here - there's still some muddying of low contrast detail such as foliage, there is very slight corner softness at the widest aperture and the images are very slightly over-sharpened, but given the pricing and specification there is more to like than to complain about.

Purple fringing has been all but eliminated (though you will still get some in extreme circumstances) and we found little if any of the chromatic aberration seen in a couple of our studio/lab tests when examining 'real world' images.

Color fringing

We found very little evidence of purple fringing in any of our real-world shots - where there is some it is only in overexposed areas, and tends to be visible only at the very edges of shots taken at the wider end of the zoom.

100% crop 35 mm equiv., F3.5

Highlight clipping

As is common with small sensor, high pixel count cameras, the A700 struggles to capture the full range of brightnesses in scenes with a large dynamic range (high contrast, very bright days). As with other PowerShots, the A700's problem seems to be a combination of slight overexposure of contrasty scenes, and a fairly steep tone curve, which can lead to quite harshly clipped highlights (and in some cases clipped shadows too). We found the problem could be minimized by careful use of AE compensation when the metering got it wrong, but this is hardly a completely acceptable situation, as clipped highlights can be difficult to spot on an LCD screen. To be fair, the problem wasn't widespread, but was prevalent enough to merit mention here. We also found in bright conditions that some channel clipping occurred (mainly reds) when shooting very bright, bold colors, though this can be overcome by reducing the saturation setting.

100% crop 35 mm equiv., F4.0
100% crop 35 mm equiv., F4.0
100% crop 35 mm equiv., F4.0
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