How to extract black fonts from gray background?

Hello,
I have a TIFF file of a scanned microfilm page of a very old manuscript.
The background of the black fonts is gray, and it makes the reading of the text very hard.
Here's a link to a sample from the page:
http://img2.tapuz.co.il/CommunaFiles/14072176.tif
My question is: is there a simple way to extract only the black fonts of the text, or otherwise to brighten up the background? I must say I am far of being an expert in image processing.
Many Thanks,
Ofer

I downloaded and played with it a bit and because of the poor quality you will not be able to get much without some eraser and paintbrush clean up, but


In photoshop open the image and go CTR+L to bring up the levels pallet...
at the top put in the following #'s 153 1.00 169 in the three fields

Click ok


Now zoom in and get out your paintbrush and eraser and start cleaning it up.

Many many thanks.