Originally Posted by Jellby
Of course, you all know re-saving a JPG image as JPG again will only reduce the quality (even if you save it with a higher "quality" setting), so this should be done with the starting source images (either scanned, or large JPGs, or whatever).
True, but it opens up a question of how far we are ready to go with the quality of raster images?
The current technology for screens of dedicated reader devices is what it is. On 600x800 eInk screens, the loss is negligible. For those who read ePubs on computer screens, the situation is quite different.
Now, considering the perfectly probable emergence of high-resolution, full-colour screens for mobile devices a decade from now, do you go with the maximum resolution (and quality) for materials that you scan, future-proofing your publication? Lossless compression?