Well we use a Canon camera that uses a RAW file type called .cr2.  But was just looking in pw5 and I see only a RAW .NEF .CRW or .DNG

I usually convert our RAW  .CR2  to TIF

And I use ISO 50  for low picture noise.

I was using a Nikon D300 that creates NEF RAW files.  However my Nikon D50 also creates NEF RAW files - but they are not the same.  For a start Photoshop CS2 cannot read the D300 RAW files, they have to be converted to DNG files first. CS3 can read the D300 RAW files. I guess Adobe are not updating CS2 RAW formats.

I seem to get a lot less noise using JPEG's from my D300 and keeping everything in 16bit TIF through Panoweaver, Photomatix and Photoshop then back to Panoweaver. Of course I'm talking HDR images.