Need some help capturing line drawing from graph paper

[Redrobes]

If you have scanned them in color or greyscale then keep them like that - i.e. dont drop them to two color yet as most of the techniques to get rid of the graph lines need something to key on. What we use depends on what you have but will either be color or luminance. You also need high res too so no dropping the res to upload here - we can take up to about 5K pix square which is pretty big. Also PNG would be better than JPG but there is a 4Mb or so file size limit too. If you cant manage to upload it all then a small section is better than a rescaled page and we will show what to do for you to replicate that on the whole page.

[YazzieGirl]

Redrobes and Gidde ~ I have edited the original post with a small selection from one diagram. It is a jpg, could change it to png, if needed.

[Redrobes]

Ok, your in big trouble here. The problem is that because they are photocopied then its turned all the lines into uniform color so there is no color difference between what you want and what you don't want. Next is luminosity - same. Its either black or white. That leaves the pattern and the pencil lines are about as thick as the grid which is also difficult to distinguish between them. So your not left with many options. I have a very special program which is not part of Gimp native but can be accessed with some extra plugins or something - I dont do Gimp. Anyway, this program looks for a grid like pattern and then removes it but in that process will remove some of the line info as well. You have the almost pathalogical case to deal with.

Can you get the original non photocopied versions of the maps and get them scanned in with a flatbed in color or at least greyscale so there is something to key on. Here is my best shot. Its not very good I would admit.

[YazzieGirl]

Redrobes - this is precisely what I thought was going to be the case ... I will see if I can get my hands on the original drawings (I work remotely, so this may take me some time).

I am more familiar with CorelDraw than I am with GIMP. Are there other open source softwares that may be better suited for this project?

Thank you for your help!