Black and White PDFs

There seems to be an increasing trend for PDFs and websites to use grey text instead of black. Even Google Sites is doing this (sorry I can't override this!).

For PDFs, there is an easy way in most PDF readers to increase the contrast of a page to force text to be black and the background to be white - perfect for reading and printing. 

Here are the steps for PDF Xchange Viewer:

Edit > Preferences > Accessibility > tick "Override Document Colors" > tick "Use Custom Color Scheme" > tick "Text Color" > Text Colour: select black colour > OK.

Similar steps are available for Adobe PDF Reader. For instance, see: https://www.quora.com/How-do-I-adjust-contrast-of-a-PDF-in-Adobe-Acrobat-Pro-9?share=1

If the PDF is an image, then you can increase the contrast by printing to PriPrinter and editing the contrast and brightness.