Before I discovered the potential of RAW, I thought that people saying "I shoot only RAW" are bunch of posers. But, to put it simply: imagine two computers. One is the tiny processor hidden inside your camera. The other one is modern dual core, 4GB RAM, fast PC or MAC machine. The camera CPU has to reach a difficult compromise between:
- quality of processed photos
- speed of processing
- low generation of heat
- being as tiny as possible
The effect is that the inside-camera processing unit cannot process image into JPG efficiently enough. Whereas a powerful PC can. That's it's better to shoot RAW.
More features:
- dedicated software can remove noise from RAW more efficiently, because the RAW is not JPG-modified at all which makes the noise more recognizable
- dedicated software has better algorithms of recognizing and removing purple fringing and other artifacts
- and more and more and more posted in RAW vs. JPG