Thanks for uploading an example image: may I make two comments:
First, in general in a case like this it would be easiest to find the optimum actions, and values to be used when relevant, using a windowed software such as XnView MP or XnView Classic, as settings can be tried quickly and the result seen immediately.
Second, do you really need to resize the original image (reduce the pixel dimensions), which will often inevitably reduce the image quality ? If the file size is an issue, there may be better ways of obtaining the result you need: I have attached a TIFF with CCITT G4 'Fax' lossless compression, which will open with image quality identical to the original image, but has a very much reduced file size.
Your TIFF file is black and white (1-bit colour depth) which precludes darkening using the above methods, however there may be a way of obtaining some improvement by other means such as use of a filter. If he has time, XnTriq could possibly advise...
Otherwise, scanning or faxing the original paper with different settings would help, which may of course be outside your control.
Last edited by XnTriq
on Mon Feb 26, 2018 8:00 pm, edited 1 time in total.
Reason: Attachment removed due to confidential information