RAW images

Article courtesy of http://photographyconcentrate.com/

also check out the camera manufacturers file formats here...

Raw filename extensions and respective camera manufacturers 

  .3fr (Hasselblad)
  .ari (ARRIFLEX)
  .arw .srf .sr2 (Sony)
  .bay (Casio)
  .crw .cr2 (Canon)
  .cap .iiq .eip (Phase_One)
  .dcs .dcr .drf .k25 .kdc (Kodak)
  .dng (Adobe)
  .erf (Epson)
  .fff (Imacon/Hasselblad raw)
  .mef (Mamiya)
  .mdc (Minolta, Agfa)
  .mos (Leaf)
  .mrw (Minolta, Konica Minolta)
  .nef .nrw (Nikon)
  .orf (Olympus)
  .pef .ptx (Pentax)
  .pxn (Logitech)
  .R3D (RED)
  .raf (Fuji)
  .raw .rw2 (Panasonic)
  .raw .rwl .dng (Leica)
  .rwz (Rawzor)
  .srw (Samsung)
  .x3f (Sigma)