scanning tiny manual

Actual manuals ar usually very tiny, even hard to read with loupe. its so tiny that it has to be enlarged. I dont know if i am stupid or not uptodate. First tried to scan with winscan2pdf(new version available) and then with pdfviewer which has a scan-option.
But i was not able to crop my subject. yes for viewing and there is a zoom(dont know anymore in which app). but output was the same 1:1. yes with pdfviewer i could crop output. but want a ready-sized file to fullsize print. Thanks