White Balance

As well as the default auto setting, the A10 has four white balance presets (daylight, shade, tungsten, and fluorescent) and a manual/custom setting that can be used with a white or gray card to accurately measure the color of light in a scene. Our standard studio tests showed the A10 to be fairly reliable, and real-world shots rarely suffer from white balance problems though inevitably in low incandescent lighting there is a distinct orange cast).

Incandescent - Auto WB
Red 6.3%, Blue -10.8%
Incandescent - Incandescent preset WB
Red 2.3%, Blue 0.6%
Fluorescent - Auto WB
Red 1.7%, Blue -3.9%
Fluorescent - Fluorescent preset WB
Red 0.9%, Blue 0.8%

Flash Performance

No real complaints here. The range is acceptable for short range social shooting (around 0.20 ft - 16 ft using auto ISO), and color and exposure very reliable. The flash throttles down fairly well at short shooting distances, and you can turn down the power using the 'Soft Flash' setting for closeups. The positioning of the flash so near to the lens means red-eye is fairly common unless you use the red-eye reduction system (there is also the option to remove red-eye from saved shots), and our only real problem is that fairly pedestrian recycle time.

Skin tone Excellent color and exposure Color chart Excellent color and exposure

Macro Focus

The A10 has two macro modes; standard macro (closest focus 12cm / 4.7-inches), usable only in the wide to mid-zoom range (up to about 55mm equiv.), and super macro (closest focus around 6cm). The Super Macro mode fixes the focal length at the wide end, but does allow some pretty impressive close ups for such a small camera.

Super macro - 61 x 45 mm coverage
54 px/mm (1359 px/in)
Distortion: Low to average
Corner softness: Average
Equiv. focal length: 38 mm
Mid Zoom macro - 75 x 56 mm coverage
43 px/mm (1101 px/in)
Distortion: low to average
Corner softness: Average
Equiv. focal length: 114 mm

Barrel and Pincushion Distortion

The A10's 35-105mm equiv. lens exhibits noticeable barrel distortion at the wide (38mm equiv.), but at around 1.1% it's not serious enough to mar 99% of normal real-world shots. The distortion gradually falls as you move up the zoom range, but there is still a small amount (0.4%) of measurable barrel distortion at the long (105mm equiv.) end of the zoom range. Considering the unique sliding design of the lens distortion is very well controlled at all but the widest zoom setting.

Barrel distortion - 1.1 % at Wide angle
Equiv. focal length: 38 mm
Barrel distortion - 0.4% at Telephoto
Equiv. focal length: 114 mm

Specific image quality issues

Overall the A10's results - when it gets everything right - are superb; detailed, clean, sharp (without being over-sharp) and with fairly subtle processing and natural color that mean the images are well-suited to post processing. The contrast is less steep than we tend to see in this class (so burnt out highlights are less common), and default saturation and sharpening levels are more or less spot-on. There is very little evidence of color fringing or chromatic aberration, edge-to-edge sharpness is excellent and at ISO 50 particularly, the results are very clean indeed.

Of course it's not all good news; the A10 suffers from slow focus, meaning i got a higher than average number of out of focus shots (due to simply pressing the button too quickly), especially in low light, and the exposure system is far from foolproof, often producing mild under or over exposure with unusual subjects. The former is easily fixed in Photoshop, but overexposure is never easy - or even possible - to fix. I would estimate my failure rate with the A10 to be around 10 per cent; higher than I'm used to in this type of camera.

Other minor niggles include a propensity to use very small apertures rather than high shutter speeds in good light (in program mode), meaning softer results due to diffraction effects and the danger of mild camera shake. This is a camera that produces its sharpest results with the lens near to or at full aperture, so it may be worth trying it in 'sport' mode if you find it choosing F9 when you'd rather have F4. Finally, as noted below, the Shake Reduction system - occasionally - fails completely, which doesn't inspire confidence (this happened in around 1 in 80 shots).

Highlight clipping

Unlike some of its competitors (which clip highlights in virtually every bright scene), the A10 manages to hang onto highlight detail fairly well, but there's only so much dynamic range in this sensor, so inevitably you will see some burning out of bright areas on occasion.

100% crop 38 mm equiv., F2.8

Camera shake

It's unusual for us to mention camera shake in the image quality section, but there are times (fairly rare, thankfully) where the Shake Reduction system appears to get it completely wrong; the examples below are surprisingly shaky given the shutter speed and focal length combination. We failed to recreate this in the studio, and I suspect it happens when you shoot too quickly.

100% crop 114 mm equiv., 1/200 sec
100% crop 38 mm equiv., 1/160 sec

Shake Reduction

The Optio A10 is the first Pentax compact to offer mechanical image stabilization (Shake Reduction) using a very similar CCD-shift system to that used by Konica Minolta in its Dimage series. By placing the CCD sensor on a movable platform the system can compensate for a certain amount of the blur caused by camera shake at lower shutter speeds and longer focal lengths. The system works by analyzing input from two internal gyro sensors and producing an inverse movement in the CCD.

In use we found the system to be effective, though by no means foolproof, and certainly not as consistently capable of reducing the effect of camera shake as other systems we've tested, particularly those that use moving lens elements rather than a moving CCD. There is no doubt that the system reduces blur, but it just doesn't inspire total confidence, especially at longer focal lengths. It also seems much more effective when the shake is in a single direction (up and down or left to right) than when it is more random.

This is in stark contrast with the optical stabilization systems used, for example, by Panasonic, which allow shots at 1/15 sec at much longer focal lengths. We also found the system to occasionally (though thankfully rarely) fail dramatically (see above). There is no doubt that SR works, and it significantly decreases the proportion of shots ruined by camera shake, but having looked at the results when I got back after a day's shooting I wouldn't say I would trust it unquestioningly.

Below are a couple of comparative 'real world' examples. Note also that all the images in the samples gallery are hand held.

114mm equiv, 1/13 sec
Shake Reduction on Shake Reduction off
114mm equiv, 1/4 sec
Shake Reduction on Shake Reduction off
38mm equiv, 1/4 sec
Shake Reduction on Shake Reduction off