Darken text on pdf

[IMANUT46]

I have several scanned pdf's that the text too faint. I was told that l could use Adobe Acrobat, but I couldn't get it to work. Is there anything I could use to darken text that is relatively simple.? Thanks.

 

[Rukbat]

Not that I know of. Not even the full Acrobat. (Acrobat Reader doesn't allow you to change much in the document.) They would have to be rescanned, and scanned properly, to give you darker text. (If the original text is light, taking a monochrome (black and white - no grey scale) picture of it under different color lights may darken it with one particular color. Then you can scan the picture. (That's part of CSI work.)