The two front runners for opening raw files in linux are Darktable and RawTherapee.
http://www.darktable.org/
http://www.rawtherapee.com/
They are both actively being developed and both have extensive tutorials.
https://pixls.us/software/ has a thorough list and links of photography software in the FOSS world.
http://www.darktable.org/
http://www.rawtherapee.com/
They are both actively being developed and both have extensive tutorials.
https://pixls.us/software/ has a thorough list and links of photography software in the FOSS world.