Seeing right through it

When scan­ning text or images from a pub­lished source, the mater­i­al on the back of the page can show through and be dif­fi­cult to elim­in­ate. This is not helped by the fact that most flat-bed scan­ners have a white sur­face under their lid. Place a black sheet (print your own if neces­sary) face down on the back of the page to be scanned. This will swal­low the unwanted ‘show-through’ into a uni­form grey back­ground in the out­put, which is eas­ily cor­rec­ted out using the bright­ness and con­trast con­trols in the scan­ning soft­ware or an image edit­or such as the excel­lent and free Gimp. This works best when the offend­ing mater­i­al is black or gray­scale, of course, but it will at least improve things with col­our mater­i­al.