Overall performance is always an IXUS strongpoint, and here the 970 IS lives up to its pedigree. It starts up in a brisk 1.5 seconds, and shuts down again just as quickly. In single-shot mode at the highest quality setting it can maintain a shot-to-shot time of 1.8 seconds, while in continuous mode it can manage approximately 1.5 frames per second, which is pretty good for a 10MP camera. Power is supplied by a relatively large 1120mAh Li-ion rechargeable battery, for which Canon claims an impressive 320 shots on a full charge. I took around 100 shots over several days while testing the camera and the charge indicator was still showing a full three bars.
As I've mentioned, the AiAF autofocus system is a bit hit-or-miss, but in centre-spot AF mode focusing is generally very quick and accurate in good light. Unusually for Canon camera it seems to have some problems focusing at telephoto zoom settings, and its low-light performance isn't as good as I had expected either. It will focus in low light, but it sometimes takes several tries to succeed. However at least it tells you very quickly that it can't focus, rather than hunting around for several seconds as some rival models are known to do.
The main saving grace for the IXUS 970 IS is its picture quality, which is well up to Canon's usual high standard. The JPEG files it produces average around 5MB each, which is large for a 10MP compact, and images are virually free of compression artefacts.
Exposure metering is seldom less than perfect, and the camera copes well with shadows and highlights despite its rather small and densely packed sensor. Colour reproduction is superb, with good detail even in very bright yellows, something that can be a problem. The lens performs well, with excellent centre sharpness, although it does produce quite a lot of barrel distortion at the wide-angle end, and there is some visible chromatic aberration in the corners. I did find the 37mm-equivalent wide-angle setting to be a bit restrictive after reviewing several 28mm wide-zoom cameras recently, but the 185 telephoto end is very useful for a bit of extra magnification on more distant objects.
Canon's Digic III image processor has proven its worth in a number of previous models, and here it provides outstanding noise control, producing images at 800 ISO that are virtually free of colour noise, showing instead a pleasant fine-grained texture that would still produce very good prints. The 3200 ISO high-sensitivity scene mode is a bit of a waste of time though, since it restricts image size to only 1.9 megapixels, and even then the quality is very poor.
The Canon Digital IXUS 970 IS is a logical progression in specification from the earlier IXUS models, and its list of features is impressive. Build quality, performance and image quality are certainly up to the usual standard, and the extended zoom range is very useful. However the awful handling and horribly designed controls limit the appeal of what could have been an outstanding if rather expensive camera. Compared to other models in the same range it is a bit of a disappointment.