Suggestions for darkening text on poorly scanned PDF files

I was wondering if anyone knew of a way in which I could darken text on a poorly scanned PDF file? I have lots of old scanned documents from back in the day before I had a good scanner (or knew what I was doing) in which the text is insanely light and really difficult to read. I have Acrobat Pro 8.1.1, if that matters at all…

Any suggestions would be greatly appreciated… Thanks!

If you have access to Photoshop Elements, from levels, you can use “set black point” and the eyedropper tool to select the text to darken it. In Graphic Converter, you can adjust the levels to darken everything and then use “set white point” from Effect to lighten the background. If you don’t have those, I think Gimp is free, but I don’t know how to use it!


Yes, technically this could be done via Photoshop (or Elements), but that’s not realistic for my situation, as I have dozens of excessively ‘light’ PDf files, many of which have lots and lots of pages, and the method you described can only be used to do one page at a time…

Anyone else know of a tool out there designed to batch-alter the appearance of imaged pages within a PDF?