differences in raw formats?

All cameras are in effective megapixals so this means they all do some kind of manipulation to get all the pixals. All seam to have different raw formats, what is the difference in raw formats? I will be working in Photoshop. I usaly save my work as a Photoshop document. Are there any advantages in saving as tiffs?

I'll try...

Not sure exactly about the "effective" mp rating, but I read something about Nikon's D1X being able to get higher resolution after the firmware upgrade because it could use more pixels around the edge of the sensor or something...

RAW formats are all different between not just camera mfr's, but different models of camera too. Adobe Photoshop CS has a raw converter that works with many of the current ones, but not all - and not many of the older ones. Camera mfr's aren't interested in helping someone like Adobe with their software so they have to reverse-engineer it. That's the whole deal behind the new DNG format (digital negative) by Adobe - they'll license it free to the camera builders and you can download a free converter. So far no takers on the camera end... Not a big deal if you always have the program (like Nikon Capture) that works with the camera's RAW files, but if you can't find the disc, computer crashes, etc - then you could have a bunch of unreadable files. With DNG, the thought is that since it's a standard this problem would be almost eliminated. Good article about this in the new Digital Photo Pro magazine (Nov/Dec I believe).

You can save as either a .PSD or .TIFF, they are both uncompressed files unlike a jpeg. I'd use a TIFF though (as your master copy) instead of a PSD because a TIFF is more universal - kind of like what I explained above. I think some old versions of Photoshop created PSD's that can't be read by the newest versions - someone verify?