Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
The key to getting first-rate image output on any operating system is setting up a good workflow. One piece of the workflow puzzle that used to be out of reach for Linux users is device profiling -- accurately measuring hardware devices like scanners and monitors to account for their differing capabilities. But a relatively young open source application called Lprof does a professional job at that task.
At good workflow ensures that every stop the image file makes along its journey -- scanner, digital camera, editing software, monitor, printer -- is a known quantity, so the color management system can apply the correct transformation to the image at each step.
Often the very first step is a scanner, which can be quite tricky. Every model is different, there are variations among every device of the same model, and a scanner's characteristics change over time. The way around such problems is to make a scan of a tightly controlled target image for which you know the correct color values. You can then measure the scan against the known values and create a device profile that a color management system can reference for all scanning jobs.