SaveAs with less data

[harry.twomey]

If i make a backup of a project, using save as, i tend to overwrite the previous backup. I would think the data of the scans and pictures doesn't change, there is probably just has a separate file containing the translation and regoining stuff.

So if the biggest file are not being modified why are they being copied again? Can't we get a system that's a bit clever and recognizes that if a file in already in the project folder and has not been modified, it can stay, and at the end recognizes the file that are not needed and delete them?

I have projects that take 20 mins to save, but if the system worked like above, it might take 2 mins, more if new scans are add sure, but it could be a lot better