Not an expert by any means but this might help http://www.photoshopessentials.com/photo-editing/raw-vs-jpeg-for-photo-editing/
One of the downsides with raw is that some of the time they look worse than the jpeg as no processing has been done on them, this may mean that you have to fix up every photo you take. Most cameras will let you capture both raw and jpeg though so that you get an instant processed image and then for the ones you want to go to town on you have the raw data. I toyed with raw in the past and just went back to jpeg. Maybe it's time to revisit it.
A tad late in replying sorry, the article on Raw vs JPEG just about covers it all, Basically you will need Camera Raw prog to manipulate the photo then open it into Photoshop, so a bit more messing about than just dealing with a straight JPEG photo. Shooting in is Raw is amazing in that once you have pressed the shutter the whole image is recorded, so if for example you have totally under exposed the shot, you can open it in Camera Raw and change exposure values there. If the same photo had been shot in JPEG it would be lost. Some people get a little bogged down here, is it better to shoot in Raw or JPEG, well are you good with the Camera or good with Photoshop.
It's still better to get the exposure right in the camera, as you'll lose some quality by adjusting it later, but RAW will let you correct things like colour balance in post processing without losing image quality.
I have used the free Canon raw editor which seemed ok for playing around. The WB picker tool is handy. But I'm no pro user though.
I find this suggestion pretty good (There's a free copy of Photoshop out there - Older one, but genuinely free, not pirated!) http://www.gtpdesigns.com/design-bl...-color-correct-underwater-photos-in-photoshop Mark
It's not genuinely free. It's out there for people that already own a license but are unable to activate this due to the activation servers being shut down.
Powerful but a pain in the ass to use. I'm no expert in Photoshop but I can handle my own but in GIMP I'm next to useless, I have to Google most tasks.
