You will need several things at least.
1. A program to copy your images from the camera into PC, especially if
the device is not seen as USB drive. Maybe gphoto will be of help.
2. I would recommend you shooting in RAW. In order to import your photos
directly in GIMP or process RAW standalone you will need UFRaw
with graphical user interface or dcraw
as a command-line tool.
3. Also camera profiling tool will be be helpful if you do not find
ready profiles for your camera model.
> I'm thinking of moving into the 21st century and getting a bottom-end
> digital reflex, preferably Pentax for the sake of nostalgia. Can anyone
> advise me from a technical point of view as to what I need in order to
> be able to get pictures into GIMP for editing? I use Slackware 11.
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