On the whole the EX1500 is a very good performer, with good resolution and a very good colour balance (the only time the white balance was fooled was in a night shot which it turned very red). In fact I was impressed by how little I had to correct colour balance on images taken with this camera, as with all digital cameras image contrast was "improved" by correcting levels (a Photoshop term) but (except when using the flash) colour balance was nearly always spot on.
Much talked about and a little mis-understood is effect is barrel distortion. Barrel distortion is a lens effect which causes images to see 'spherised' at their center. Most noticeable when you have a very straight edge near the side of the image frame. Some people find this to be an unacceptable fault of the camera, my own personal feelings are that although barrel distortion can be visible sometimes it would not be noticeable for 99% of your photography. That said, this camera certainly has barrel distortion at it's widest angle (38mm):
CCD / Electronic noise
Anyone who has read my previous reviews will know that my pet hate is CCD noise, I have come to the conclusion that I may have been "spoilt" by cameras which exhibit hardly any noise (Nikon CP900s, Canon Powershot Pro 70). It's something I've had alot of critisism over (read: Sony FD-91 review).
What do you mean by noise? I think I need to qualify what I mean by noise and where and when it's important, CCD noise can be seen in an image when zoomed in 2 x or 3 x as a grain or random colour pattern on what should be a continuous tone of colour. Because of it's characteristics it is normally more visible in dark areas of an image or when an image is taken in low light withouta flash.
When does / doesn't it matter? If the majority of your images are reduced (resampled) down for use on a web page, in an email or just to make them easier to view on your monitor then the actual action of resampling the image down by 50% will (most of the time) average any noise produced by the CCD / Electronics and you'll have a very clean and "continuous tone" image. Of course, the original image resolution is important (this is why noise on the FD-91 was such an issue because it only has XGA resolution, downsampling to 640x480 didn't average the noise out). Noise really only matters if you want to take a section of the image and blow it up or you need to print the image at anything less than 300dpi.
Back to the EX1500, it does indeed exhibit some noise, although fairly slight it is definitely still there. If you browse through the samples galleries you'll see images which have been reduced by 50% which look perfectly (in fact, very) good. Take a close look at some of the untouched images.
This image of a Singapore "shop house" looks prefectly acceptable at this resolution, however zooming in on the marked area of the original by a factor of three demonstrates the random "colour noise".
"Stuck-on" pixels on very long long exposures
I don't really want to highlight this as a problem, one of the great things about the EX1500 is it's ability to take very long exposure images (up to 2 seconds - which is long for a digicam) and great for night time shots.
However, this also reaches the extremes of performance of the CCD, on the long exposure image shown below (about 1.5s) I have indicated pixels on the CCD which have maxed-out and can be seen as a bright red, blue or green dot.