Factory Canon firmware JPG format | CHDK firmware RAW format |
These both pictures has been taken by Canon SX100 IS camera. First picture has taken as usual camera photo in JPG format. Second has taken with helps of CHDK firmware in RAW (CRW) format.
As you can see it has a lot difference. Second is more detailed.
Now I'd like to talk about CHDK firmware. CHDK is a firmware extension for Canon Powershot / Digital IXUS cameras. It's internal camera software in addition to standard, it has a lot improvements and various settings, many of these very useful. More detailed descrition you can see there http://chdk.wikia.com/wiki/CHDK_firmware_usage/AllBest. Information about installation there http://chdk.wikia.com/wiki/CHDK_for_Dummies.
Latest version can be downloaded there http://mighty-hoernsche.de.
After shooting you should do something with your CRW image, it isn't easy because needs some knowledge in photographic area. I've used RawTherapee software, it's under GPL, so is totally free now.