Let’s start with some jargon busting, it always helps to have a better understanding of industry terms when delving into the unknown.
File formats- Document scanning means converting your paper into electronic formats such as:-
PDF (Portable Document Format) is a file format that has captured all the elements of a printed document as an electronic image that you can view, navigate, print, or forward to someone else. PDF files are created using Adobe Acrobat, Acrobat Capture, or similar products. To view and use the files, you need the free Acrobat Reader, which you can easily download. Once you’ve downloaded the Reader, it will start automatically whenever you want to look at a PDF file.
TIFF (Tagged Image File Format) – TIFF is a common format for exchanging raster graphics (bitmap) images between application programs, including those used for scanner images. A TIFF file can be identified as a file with a ‘.tiff’ or ‘.tif’ file name suffix. One of the most common graphic image formats, TIFF files are commonly used in desk top publishing,
JPEG (Joint Photographic Experts Group) – The JPEG format offers a compression scheme that makes the image file smaller than files in other formats by discarding some of the image information. Most commonly used for scanning photos
PNG (Portable Network Graphics) – A lossless file format created to overcome deficiencies of the Graphics Interchange Format (GIF), such as the limited number of colours. This format is typically used in web images as it retains its quality while staying a relatively small file size. Most scanning bureaus will have specialist software that can use a document scanner and convert images into any one of a number of different formats, and depending on the application that you need the files for the format you choose may be different.
DPI (Dots Per Inch)- The resolution of a printed page, expressed in the number of printer dots in an inch, abbreviated dpi. Scanner resolution is also expressed, somewhat in accurately in dpi.
PPI (Pixels Per Inch) – The number of pixels captured per inch by a scanner. This is a more accurate rate term than dpi (dots per inch) when applied to scanners because scanners capture pixels.
SPI (Sample Rate or Samples Per Inch) – The number of pixels per inch captured by a scanner. Resolution – The number of pixels or dots per inch in an image. Also the capability of a scanner to resolve detail, which requires quality optics as well as high ppi or spi.
If you have detailed graphics images then to retain detail you may consider using 300dpi or even 600dpi and these could create very large file sizes depending on the format chosen. Raster Image – An image defined by rows and columns of pixels. Scanners capture images as raster images, although some can convert them to vector images.
Raster to Vector Conversion – The process of examining a raster image for lines and strokes, and creating a new image that looks the same but is made up of lines rather than pixels. When a person draws, they are creating a vector image. Vector images can be enlarged much more accurately and often have a smaller file size.
The next consideration is file size, typically scanning text in 150 dpi (dots per inch) will generate relatively small file sizes especially in PDF format and can be converted using OCR (optical character recognition) software to edit in packages such as Microsoft Word.
Other software tools that are available can perform tasks such as deskewing (straightening the image) removing unwanted marks or lines on the pages, adding page numbers or file names to the documents Ideally a good document or digital scanning project delivers the best image quality to match the requirements with the smallest file size to meet that specification