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Digitizing and Geocoding Old Maps?
alobar72 writes "I have quite a few old maps (several hundreds; 100+ years old, some are already damaged – so time is not on my side). What I want to do is to digitize them and to apply geo-coordinates to them so I can use them as overlays for openstreetmap data or such. Obviously I cannot put those maps onto my €80 scanner and go. Some of them are really large (1.5m x 1.5m roughly, I believe) and they need to be treated with great care because the paper is partly damaged. So firstly I need a method or service provider that can do the digitizing without damaging them. Secondly I need a hint what the best method is to apply geo coordinates to those maps then. The maps are old and landscape and places have changed, it maybe difficult to identify exact spots. So: are there any experiences or tips I could use?"
Why not use a handheld scanner and some stitching software?
I suggest you contact the restoration experts in major museums for (1) advice about preservation, and (2) how they go about their own digitizing projects. I read a fascinating article about the digitization of many medieval parchments, but I don't recall the particular museum involved now.
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I doubt it's in the US :) Based off the currency he used for his scanner (€80) I'd say that he's somewhere in Europe :) Good suggestion though. I wonder if the country he is in (or Europe in general) has a similar organization.
Vivin Suresh Paliath
http://vivin.net
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You might want to find the local university cartography or geography department. They will probably already have a method of doing this, or at least could point you to someone who does. Here's an example: http://mapmaker.rutgers.edu/ and their historical maps: http://mapmaker.rutgers.edu/MAPS.html
-molo
Using your sig line to advertise for friends is lame.
Well, that's certainly true if you apply a specific scale to the map, but another method would be to attach geo-coordinates to landmarks on the map and then use interpolation to determine location otherwise.
In this way, if you were "moving on the map" between two locations that are a different distance apart on the map than reality, your "dot" would just move faster. Positional accuracy would be a continuum that increases in accuracy the nearer one is to a particular point of interest.
Perhaps you could use morphing software to morph identifiable key points on the map to the same points on a modern map?
Seconded. Get some quality gear. As in, contact your local university or museum, they are bound to have (connections to some place with) the proper equipment.
What's this for? If you would be willing to donate digital copies, or even the originals (if you feel they would be better able to take proper care of them), I bet they would gladly provide the time and resources.
Good luck!
"Good news, everyone!"
If you are having a hard time finding a surveyor, just go to the closest construction sight and find a guy that looks like the sun has baked him into beef jerky and that has orange and pink ribbon hanging out of his truck.
If you are not really certain, just ask him where the closest pcc is and he will give you an hour long spiel about the advantages of pccs over spirals.
At this point you should realize that you would rather talk to a GIS professional than a Surveyor, if only to save your sanity. Trust me, I have been both and LS's can be a drag.
Wherever You Go, There You Are
"First off, practice all of this on layed out newspapers while developing your preferred methodology. "
If you use laid out graph paper you'll be able to tell how much distortion you're introducing into your "scans".
Although it's not totally clear from his phrasing, I believe that he meant to avoid rivers and coastlines, but he phrased it badly.
It's called rubbersheeting & and some GIS suites can help you do it, or have extensions that will. Pretty sure AutoCAD Map can do it too if you have Raster Design installed.
http://en.wikipedia.org/wiki/Rubbersheeting
There is a war going on for your mind.