Overall Image Quality

I was very impressed by the Digital IXUS 300, it's a tiny little package which can deliver the goods just like it's bigger counterparts. Resolution was very good, as was (in natural light) white balance, images exhibited very little noise, indeed up close gradients were smooth and clean with very little noise"speckle". The IXUS 300 had a tendency to overexpose in certain circumstances, generally an exposure compensation of -0.3 EV when shooting outdoors counteracted this metering curiosity. Some people may find the images a little soft, but it's clear that Canon's new philosophy of leaving the sharpening decision to the photographer in the digital darkroom has made its way into the IXUS 300's design.

Maintaining shadow detail

Original image, good for printing, shadow detail maintained Contrast adjusted image, perfect for the monitor, less ideal for printing

Something else inherited from the G1/Pro90 is the attempt to maintain as much shadow detail as possible by maintaining the dark end of the grayscale at about 10%, this means that no dark detail gets clipped by over enthusiastic contrast algorithms, this leads to a neutrally balanced and fairly "flat" image.. This balance of image works perfectly for printing, indeed some of the thought process behind it may be to do with Canon's new direct-connect printers, but mostly I think it's just to maintain detail were it would normally be clipped. Obviously this means that if you want your images to have real contrast (black is black) you'll need to do a little level correction on some of them (Photoshop; Image > Adjust > Auto Contrast; will do this fairly well).

Colour saturation

Original image, low contrast, low saturation Contrast corrected, saturation boosted +15

One area of disappointment for me were slightly pale colours (low saturation), to give the image the zing (colour "punch") it deserved I nearly always had to push up the colour saturation of an image by about +15 (Photoshop; Image > Adjust > Hue/Saturation > Saturation +15).

Purple Fringing (Chromatic Aberrations)

Surprisingly good news here! For such a tiny little lens the IXUS 300 exhibited almost NO visible chromatic aberrations, yes it suffers a little from blooming (the overflow of charge from saturated pixels) which you can see below, but this shot taken with a camera with chromatic aberrations would have large purple highlights around the branch detail. Whether Canon are doing this through post-processing or its down to the lens / sensor design is inconsequential we have to give some Kudos to Canon for virtually eliminating one of our biggest complaints.

Visible chromatic aberrations in an "every day shot"
Our now standard chromatic aberration test shot *

* I'm not totally happy with this shot, it's the best one we got, unfortunately the IXUS 300 simply didn't want to focus on our completely black test chart let alone produce an effective +2.0 EV overexposure, so please don't use this image as reference against another result.

Barrel and Pincushion Distortion

Zero, no pincushion distortion at full tele, another excellent achievement from such a small lens. There is however visible barrel distortion at full wide angle, we measured it as about 1.1%.

Barrel Distortion, 1.1% @ Wide Angle Pincushion Distortion, 0.8% @ Full Tele

White Balance

Good news, white balance presets which actually work! Once more Canon seem to have solved another niggling problem, white balance presets which don't quite work, the sunny, indoor and fluorescent presets work well and should get you out of trouble even in odd lighting conditions. The Auto white balance only seemed to work well in natural light.

Outdoors, Auto Outdoors, Sunny Outdoors, Cloudy
Incandescent, Auto Incandescent, Indoor  
Fluorescent, Auto Fluorescent, Fluorescent