Pentax Optio A40 review

The Optio A40 is the successor to the A30, a camera that impressed us greatly in our compact digital cameras Labs (Shopper 238). It wasn't without fault, but it took attractive pictures quickly and reliably, and was competitively priced.

It's disappointing to see that the A40 increases the resolution from 10 to 12 megapixels. That might sound odd, but we've yet to see a 12-megapixel compact camera that offers significantly more detail than 10- and even 8-megapixel models. More often the noise levels, performance and price change for the worse. Here, the latter seems to be true: the A40 costs a lot more than the A30 did. However, it's reassuring to see that performance remains excellent. We managed to capture a shot every 1.4 seconds during normal shooting, and every two seconds with the flash. Continuous shooting remains respectable at 1.1fps.

Dynamic-range boosting seems to be the must-have new feature for 2008. Unlike a similar feature in Nikon's D60, the A40 doesn't reduce the exposure to capture a little more highlight detail, although this can be achieved manually with the exposure compensation control. Still, we really like the A40's implementation, as its tendency to increase noise levels is less than in other systems we've seen; the camera appears to compensate with heavier noise reduction.

We also like that there are four settings from which to choose: Off, Weak, Strong and Auto. The first three behaved as expected, but Auto was extremely effective at finding the best processing strength depending on the scene being shot. In scenes with no clipped shadows and highlights, it appeared to have no effect at all, while in very high-contrast scenes, the results matched those of the Strong setting. This means it's possible to leave the feature in Auto mode, safe in the knowledge that it will improve photos when necessary and not damage them at other times.

Sadly, some of the A30's weaker areas remain unresolved. Optical image stabilisation is built into the sensor, but it managed to keep only around a quarter of photos sharp when using a 1/30s shutter speed and telephoto zoom position. The face detection system is slow and clumsy at locating faces and the manual exposure feature could be easier to adjust. Still, having this at all on a compact camera is always welcome.

Image quality closely resembled the A30's, with pleasing exposures in a range of conditions and flattering portraits. Side-by-side comparisons suggest a slight improvement in detail, but it appears that digital sharpening plays as much a part as the extra pixels, exaggerating contrast in fine textures. Ultimately, however, detail isn't significantly better than it is from Samsung's NV8, which exhibits much less noise and is far more affordable.