An electronic document image of a document is captured using a camera of a handheld device. A user interface of the handheld device displays an instruction to place the handheld device on the document and to change the magnification of the electronic document image on the user interface until the electronic document image and the document are the same size. The handheld device automatically determines the original size of the document based on the magnification that made the electronic document image and the document the same size when the handheld device was on the document. The handheld device converts the electronic document image into an original size document image file based on the original size of the document.