This conversation has been merged. Please reference the main conversation: Lightroom/Camera Raw: Automatic scratch and dust removal
The idea is simple:
1) scan the same photo twice with rotating it (in scanner) by 180° second time, or simply with moving it a little;
2) align image contours of those two scans;
3) combine scans using darker pixels of two images.
This will eliminate white spots on scanned images made by dust.
The result will look like this:
As you can see, almost all dust has vanished, without losing details.
The images should be aligned in a same way as Photomerge does with panoramas, but please note that images will not match in all areas, because of roughness of paper or irregularity of scanner's movements.
Therefore, contours should be aligned in several areas of image independently.
Also please note that I have suggested this feature to other companies as well, for free of course.
And thank you for quality programs.