Setting the appropriate resolution is perhaps the most important aspect when scanning your documents.
The higher level of dpi (dots per inch) will dictate largely the clarity of the end result. This aspect is critical particularly if you require the scanned documents to be OCR (optical character recognition) text searchable.
Too low a resolution will mean that your software will struggle to identify the text correctly and as a result will potentially record it inaccurately or worse not at all. Whilst errors or omissions may be corrected manually, this can be time consuming and should be avoided.
Where black and white or grey-scale documents are required to be text searchable, we would strongly recommend using a dpi of not less that 300. In the case of colour, a higher resolution of 400 dpi should be considered.
Another factor you may wish to bear in mind is the font size of the original document. As a general guide, the smaller the font size, the higher the resolution should be.