clipped from: prophotolife.com   
Okay, it’s extreme time. I simultaneously shot a RAW (Canon CR2) file (left) and a large JPEG (right) of the same scene with a Canon 20D. These were shot with correct exposure but under tungsten light with the camera set to daylight color balance.
Here’s the RAW file, straight from the camera: ugly.
raw tungsten
The JPEG file looks much the same straight out of the camera.
jpeg tungsten
I put this RAW image into Photoshop CS2 (ACR), clicked the eyedropper on the gray square in the middle of the QPCard and voilá, it looks pretty darn good.
converted raw tungsten
tungsten correct raw
I opened the JPEG in CS2, opened Curves and clicked the gray square in the QPCard with the eye dropper to neutralize white balance. Ugh.
jpeg tungsten corrected
tungsten correct jpeg
RAW at -2 stops.
raw -2 stops
JPEG at -2 stops. They look much the same
jpeg -2 stops
Okay, in CS2 (ACR) I did a really quick correction to the file and processed it out.
corrected raw -2 stops
minus 2 raw detail
In CS2 I did a quick curve correction to the JPEG and got the highlights and midtones looking acceptable. But where’s the shadow detail?
corrected jpeg -2 stops
minus 2 jpeg detail