Let's talk more about the lens. It's really fast and bright, as you can open the aperture as wide as f/2.
So it's ideal for blurring the background in close-up portraits, and being able to whack the aperture right open is obviously very handy in low light.
The lens itself is of outstanding quality and we found there to be minimal distortion – a great performance for the money.
The zoom is a bit limited at 3.8x, but you quickly get used to it, and there's optical image stabilisation to keep things nice and sharp at the telephoto end. The other advantage of a limited zoom is that it gets you into the good habit of getting closer to your subject, rather than relying on telephoto trickery and suffering the inevitable distortion you get on cheaper compacts.
The PowerShot S90 is a very discrete camera, so it's great for candid street photography, where you don't always want your subject to know they are being photographed. As mentioned, it's very easy to compose shots on the generous, well-lit rear LCD.
When it comes to speed and performance, it's a mixed bag. The PowerShot S90 takes about three seconds to save RAW images, which is quite good for a compact, so we're not quite sure why it still takes a second or two to work through much smaller JPEG files.
The camera can only manage 0.9fps in continuous shooting mode, too, which limits its appeal for action and sports photography.
On a related note, it's advisable to hold the camera quite firmly when you take the shot, as it's so light, we sometimes found ourselves moving away before it had actually finished processing.