Enhancing Documents with GIMP

[johnstonsimon]

Greetings 

I'm looking to find any tips/ticks to help enhance old parish documents using GIMP. I know I can change black and white levels and brightness and contrast etc but was hoping if anyone had any luck with blending layers or some of the filters that this software has.

In particular I'm trying to see if I can get to restore some of the faded text on parish records from the National Library or Ireland, specifically the Pomeroy marriages from 1837-1840

https://registers.nli.ie/parishes/0233

Many thanks