MD HQ limits the size of file uploads to 16MB. Generally speaking, this is far more than is required for any normal document, but PDFs in particular can sometimes be far larger than necessary depending on the compression settings of the file. A well optimized PDF can be thousands of pages long and fit within the 16MB limit, whereas a very poorly optimized single-page PDF can be enormous. A few useful tips:


  • When scanning documents, set your scanner resolution to sample at 150 DPI or lower. Generally 96 DPI is sufficient to generate a highly readable document, so if it's a particularly long document you may want to reduce your settings to 96.
  • If OCR (Optical character recognition) is available on your scanner turn this on. It can dramatically reduce the file-size and has the added bonus of allowing you to copy text from the resulting scan. Some scanner settings will refer to this as "Text Enhancement".
  • If you have an electronic PDF sent to you, you can open the PDF in Acrobat Standard or Acrobat Pro to: