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Digitizing and Geocoding Old Maps?

timothy posted more than 4 years ago | from the walking-directions-rivendell-to-el-dorado dept.

Input Devices 235

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?"

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Handheld scanner (4, Insightful)

rbcd (1518507) | more than 4 years ago | (#31431416)

Why not use a handheld scanner and some stitching software?

Talk to a curator (4, Informative)

The_Wilschon (782534) | more than 4 years ago | (#31431690)

Another possibility would be a really high resolution digital camera. My wife (historical linguist) has dealt some with manuscripts, and that was their method of digitizing them for further study. OTOH, she's not a museum curator or archivist; they probably have even better methods. If you want to do it right, talk to a curator or archivist of some sort. They deal with much more fragile and much more valuable documents on a regular basis.

I don't have any good ideas to contribute about the geocoding, unfortunately.

Re:Talk to a curator (1)

David Gerard (12369) | more than 4 years ago | (#31432138)

Yep. Glass over map, good high-resolution camera mounted above (as far as possible), long steady exposure. Maybe some stitching afterwards.

Blue print company (0)

Anonymous Coward | more than 4 years ago | (#31431708)

Take it to a high volume blueprint company ("your city name" Blueprint, Dodge Plan Room, etc.)

Most have continuous feed scanners designed for E size drawings or larger, and the one next door sells 6'x10' city maps they print on site.

As far as the geocoding, I'll leave that to those more qualified.

Re:Blue print company (1)

cskrat (921721) | more than 4 years ago | (#31432142)

Except that, from the poster's description, these maps are in no condition to survive any sort of feed mechanism.

My layman's recommendation would be to follow Wilschon's advice above and use a digital camera to digitize them. You'll probably want to rig a mount system that will allow you to move the camera on a parallel plane to whatever surface you have the map on.

Depending on how accurate you want the digitization to be, you'll probably want to use much better lenses that are built in to a typical snapshot camera. You should solicit the advice of a photography expert to find out what lens setup would work best for capturing images of a flat plane at .3 to .6 meters with no distortion and consistent focus.

Re:Blue print company (3, Informative)

sdpuppy (898535) | more than 4 years ago | (#31432288)

At the least, camera with telephoto lens or telephoto part of zoom would distort the image less than a wide angle, although the telephoto aspect would create more work in that more sections of the map would need photographing and you might need to be further away from the document.

For best results generally you would use a SLR with Macro lens. This type of lens generally provides the flattest field at reasonable cost even when it is not used in macro mode.

Then you've got architectural lenses, but those cost an arm and a leg and a foot - but then again, renting is always an option...

Re:Handheld scanner (2, Informative)

Rei (128717) | more than 4 years ago | (#31431762)

I was going to suggest the same thing -- two birds with one stone. I personally use Hugin for things like that. You take many high-res, overlapping photos. You can automatically match them up with autopano-sift and then use vertical and horizontal alignment points to stretch them out as you would prefer. If the results aren't close enough to use as an overlay as-is, if you had a hires modern map, you could load it and set the FOV to roughly match up with the FOV of your fully aligned pieced-together map, and then define control points between it and your map pieces. Optimization will then stretch the pieces to try to fit to your modern map while still being pieced together.

Re:Handheld scanner (2, Informative)

mpapet (761907) | more than 4 years ago | (#31431778)

Yowza, that would be a royal pain to get results.

Two ways to go.

1. Wide format scanner. These are usually at more specialized digitization shops. Find someone who scans blueprints in your area. []
Only you can judge if the documents will be okay through the feeder. The feeders aren't hard on documents. I'd give your best one a shot. Naturally, you want to be there. So, not every service provider will be okay with that.

2. You most certainly can use a flatbed scanner. The key will be stitching software and memory/cpu resources and refining the scan/stitch method. Make them big-ish files, maybe 300ppi. After 300ppi, any information is useless for a 1:1 reproduction.

Lastly, overlaying geocoordinates info won't quite work as elegantly as you think. Ignore my doubts and go for it. I think the end result would be more art than science if done well. If done well, there will probably be a couple of false starts.

Re:Handheld scanner (5, Informative)

toastar (573882) | more than 4 years ago | (#31431930)

I do this for a living, We Use a wide format scanner and Global Mapper to georectify them.

Contact if you would like a quote.

We do everything from old torn maps to vellums to Tifs, We can Georectify them to load quickly as a geotiff. or we can digitize the data on the maps into Arc compatible Shapefiles.

Re:Handheld scanner (4, Informative)

toastar (573882) | more than 4 years ago | (#31431952)

We can also output Google Earth KML's. It's neat to be able to click a link and get all your contours and well locations to pull up in 3D. And to have this file work on any machine with google earth.

Re:Handheld scanner (5, Insightful)

Gilmoure (18428) | more than 4 years ago | (#31432140)

Or contact local university geography department. Might be able to work up some program with them to have students do the digitizing.

Re:Handheld scanner (1)

hardburn (141468) | more than 4 years ago | (#31432292)

This, please. Mod this to the sky. These maps no doubt have historical value and if they need to be handled carefully, then give it to people who are trained to do it.

Re:Handheld scanner (1)

stephanruby (542433) | more than 4 years ago | (#31432230)

Good advice so far, scan it and stitch it. Once you have that, just release it under a creative commons license, and ask for help with your goal. The crowd should be able to help you with the rest. Some will do an overlay with a fish-eye. Some will do an overlay with a small rectangular mask. Some will try morphing the different maps using the edges and/or the landmarks that can be recognized as reference points. It may not come out the exact way you originally envisioned, but with a bit of playing around with it -- something cool should come out of this project eventually.

The base software for something like this is OpenCV (OpenComputerVision), which has C++ and Python bindings, but even if you're not a programmer, and still want to do everything yourself, you should still be able to find something that's GUI-driven and easier to use than OpenCV.

Re:Handheld scanner (1)

icebike (68054) | more than 4 years ago | (#31431858)

Hand held? That would be a mess.

To the OP:

Almost every bigger city has an artist community and almost any art shop will be able to point you to people who specialize in super high resolution scanning. (For a price, but its not usually unreasonable.)

The file sizes will be huge.

Re:Handheld scanner (1)

TheMCP (121589) | more than 4 years ago | (#31432058)

For that matter, why not use a digital camera and some stitching software?

Or, if you've got a good way to align a map against the lat/lon grid (which you'll have to have or you won't be able to use the maps anyway), why bother stitching it at all? Just photograph the map in sections, and use your alignment method to align each section separately.

set course (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#31431420)

for first post

Re:set course (1, Funny)

Anonymous Coward | more than 4 years ago | (#31431502)

I guess you should have used a more up to date map.

Digital Camera (1)

mitchplanck (1233258) | more than 4 years ago | (#31431452)

Use a digital camera. It doesn't even have to be super high MP. Just stitch the images together.

Re:Digital Camera (2, Informative)

AvitarX (172628) | more than 4 years ago | (#31431674)

There has to be somewhere that does this.

Where I work we have a medium format scan back we use (it is essentially a 100 mega-pixel camera that scans across over about 15 minutes to get an image).

We are in Wilmington, DE, which is a fairly small city. I know there is a similar device in DC, which is not too far. We went to the Library of congress and actually scanned maps there as a test before purchasing it.

It actually allows for some interesting capture as one can adjust the lighting in different ways to get details a flatbed may not (we replaced a 2'x3' flatbed with it).

It could probably do the 1.5m one in two scans, and most smaller ones in one scan.

Look around your area for a place that offers art-reproduction for the service.

dig camera (1, Informative)

YrWrstNtmr (564987) | more than 4 years ago | (#31431464)

Proper lighting, focus, tripod, and a large enough flat surface should produce pretty close to scanner results.
Faster than the scanner and stitching.

Re:dig camera (1)

Hadlock (143607) | more than 4 years ago | (#31431644)

A lot of people now recommend SLRs for old/ancient family photos that have been framed. In most cases an SLR is going to give you the quality you need. For internet caching purposes, 72dpi is plenty good enough.

Re:dig camera (2, Informative)

vcgodinich (1172985) | more than 4 years ago | (#31431732)

You never print anything that you care about at less than 400 dpi (as a rule of thumb)

If you are archiving things with a 15 mp slr you are missing ALOT of detail that the prints have. I agree that prints stuck to glass are a challenge, but taking a picture with a current slr is a last ditch option.

Re:dig camera (0)

Anonymous Coward | more than 4 years ago | (#31431938)

If you are archiving things with a 15 mp slr you are missing ALOT of detail that the prints have.

Details such as, for example, the fact that "a lot" is two words.

Re:dig camera (1)

toastar (573882) | more than 4 years ago | (#31432308)

250-300 is fine for scanning, you can always drop pixels, It's a lot harder to bring them back. Always keep the Hi-res's.

Re:dig camera (5, Informative)

vcgodinich (1172985) | more than 4 years ago | (#31431686)

no no no.

Been there, fought lighting and camera distortion for hours, only to get bad quality (relative to a scanner)

Lay the maps out on a uniform surface, take the lid off a nice scanner and turn it upside down and move it place to place. Use rather big (1-2inch) overlaps, because the edges of the scanner sometimes are incorrect. You can make a batch process to crop the edges off in photoshop / gimp.

Most important is to lock down scanner settings so nothing is auto, or you will have colorcontrastluminosity differences between sections of your map.

Stitching these together requires 0 effort in any modern photographic editing software.

This is cheap, gives the best results and is the only way to get good quality without spending a fortune or damaging the documents.

Re:dig camera (1)

Jflatnote (926337) | more than 4 years ago | (#31432004)

While a camera is often a good idea for fragile documents and old photographs, because of various optical aberrations associated with camera lenses, cameras are not necessarily a good idea for geospatial documents, where distortions can put landscape features in incorrect places. This problem is compounded if adequate reference sites no longer exist for georeferencing. To capture raw raster images of the maps, there are a number of different options including 1) physically dividing the original maps into scannable portions and merging in software (cheapest, fastest, but you lose the integrety of the original documents - not a big deal if they are almost lost already - huge deal if the existence of the physical maps themselves is of particular importance (e.g. official treaty boundary maps). ; 2) Heads-down hand digitization using a tablet and stylus (takes a long time, pain in the rear, results in vector equivalent to map); 3) hire out to a shop with large format scanner (print shops, newspaper offices, even city offices may provide these services if you ask) - University geography departments are often interested in unique problems like this - might even do the rubbersheet georeferencing for you for free.

Re:dig camera (1)

toastar (573882) | more than 4 years ago | (#31432290)

Proper lighting, focus, tripod, and a large enough flat surface should produce pretty close to scanner results.
Faster than the scanner and stitching.

It's note just a flat surface, the glass also sort of forces the paper flat. You would need a large heavy piece of plexiglass for this setup as well for the crinkly maps.

Contact a Museum (4, Insightful)

Speare (84249) | more than 4 years ago | (#31431470)

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.

Re:Contact a Museum (-1, Troll)

Anonymous Coward | more than 4 years ago | (#31431508)

I suggest you suck my big fire hose cock and swallow my huge load. That's what I suggest.

Re:Contact a Museum (-1, Redundant)

Anonymous Coward | more than 4 years ago | (#31432248)

Wtf, that was pretty rude!

Re:Contact a Museum (2, Informative)

ILikeRed (141848) | more than 4 years ago | (#31431652)

I agree, you might try contacting someplace like David Rumsey Historical Map Collection [] to see if they would be interested in helping, or might otherwise make recommendations.

A collection of other links that might be of interest:
Historical Map Web Sites []

Some other good options (0)

Anonymous Coward | more than 4 years ago | (#31431716)

If not a museum, also try contacting your local university or historical society. They may also see value in your goal, and like the museum they might also take steps towards physical preservation in addition to doing digital archival.

As for doing geocoding, you might try asking those type of questions on the Google Earth forums. From what I understand, Google Earth already has some nice tools for integrating different layers of map overlay data, and it should work great for what you're trying to do.

Re:Contact a Museum (3, Insightful)

MMC Monster (602931) | more than 4 years ago | (#31431796)

How about asking the real experts: Google.

I don't mean googling for an answer. I mean actually emailing someone at google to see if the people they have involved with book scanning may have some ideas. At the very least, if you peaked someone's interest there, they may point you towards the right people in the restoration business.

Re:Contact a Museum (5, Informative)

martas (1439879) | more than 4 years ago | (#31431974)

piqued, not peaked

/grammar nazi

Re:Contact a Museum (2, Informative)

ngrier (142494) | more than 4 years ago | (#31432024)

If the maps are in decent shape, you typically use a large-format scanner. These are extremely expensive, though, so you'll preferably want to find a local university or friend at a company with one. Most larger copy shops will have one (for making architectural plans/construction documents) but will likely charge you a pretty penny to use it. And as others have pointed out, uni or a local historical society may have been through this so be relatively set up to guide you along (or even do some of it for you!).

If they're really brittle or on non-standard material, digital photography will likely be your only option. And if you want a nice orthographically correct version it will take a lot of patience as you'll get a fair bit of distortion on those large maps. So, as described by other folks in this thread, you'll need a setup so that you can take a number of tiles and stitch them together. To truly take a line from the 'pros' (as in the way they actually shoot aerial photography) you'd want to very carefully mark out a grid pattern on the map itself so you have something to correct against. One other thing: find the smallest real aperture you can get - if you've ever seen pictures from pinhole cameras you'll notice that everything is in focus. (And if you're debating using a point and shoot vs a nice DSLR, make sure to convert to equivalent focal length when comparing - in most cases you'll find that as long as the optics are decent on the P&S, the effective aperture will be better unless you have a really fancy lens/camera setup.)

That all said, if they are old, and you're more concerned with georeferencing them than having a high-quality reproduction, you likely needn't spend too much time getting a photo of the final version. As there will almost indefinitely be some distortion from the true coordinates, you'll likely need to do some 'rubbersheeting' to get the maps to match up with their real-world locations. That process will likely introduce way more distortion than that from from your digital camera. If you have access to mapping software such as ArcGIS, it will do it easily for you. Otherwise there are lots of free products out there that will allow you to distort the image appropriately.

Good luck!

Oblig: Steven Wright (3, Funny)

fahrbot-bot (874524) | more than 4 years ago | (#31431486)

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) ...

I have a map of the U.S. - its actual size. The legend says "1 mile = 1 mile".
People ask me where I live and I say, "E4".

Re:Oblig: Steven Wright (0)

Anonymous Coward | more than 4 years ago | (#31431608)

You live in the ocean?

Re:Oblig: Steven Wright (2, Funny)

b4dc0d3r (1268512) | more than 4 years ago | (#31431844)

You sunk my battleship!

Re:Oblig: Steven Wright (1)

LoverOfJoy (820058) | more than 4 years ago | (#31431882)

I have a map of the U.S. - its actual size. The legend says "1 mile = 1 mile".
People ask me where I live and I say, "E4".

That would be fun to play a long game of Risk on.

Re:Oblig: Steven Wright (0)

Anonymous Coward | more than 4 years ago | (#31431956)

I wonder how long it takes to fold that map...or do you roll it to avoide creases?

Is this in the US? (2, Informative)

Sycraft-fu (314770) | more than 4 years ago | (#31431506)

If so, give USGS a call. They may well be interested in helping you with this and obtaining data from the maps. I can't say for sure, of course, but this is the sort of thing they do. When it comes to map data for the US, they are the go to guys. Call them up, tell them what you've got and what you want to do, see if they can put you in touch with someone in their agency who'd be interested in helping.

Re:Is this in the US? (3, Insightful)

vivin (671928) | more than 4 years ago | (#31431546)

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.

Re:Is this in the US? (0)

Anonymous Coward | more than 4 years ago | (#31431628)

Good call in mentioning the USGS, but unless the person is an immigrant to the US or an extrememly comitted anglophile, I doubt they would have given dimensions in meters (sorry, metres).

Triangles (1, Informative)

Anonymous Coward | more than 4 years ago | (#31431512)

Not ALL features will change. Once you get them to a scale you can use, use three points on both maps, such as mountain peaks or a particular coastal feature. When overlaid and aligned, it should be fairly accurate.

Re:Triangles (1)

ImOnlySleeping (1135393) | more than 4 years ago | (#31432270)

Local scale coastal features are more than likely nowhere near where they were 100 years ago. The mountains I like though.

Re:Triangles (1)

vtcodger (957785) | more than 4 years ago | (#31432324)

I'm no expert on this, but I do know that several of the authors of parts of the Vermont Geological Surveys in the early years of the twentieth century, had extremely un-nice things to say about the accuracy of the USGS maps of the era. It is apparently very difficult to mark a rock outcrop on a map if you are perched on the bank of a stream and your map says you are on top of a hill. I would guess that maps of other places from the same era might be as bad or worse. If there is a land survey like the US's Public Land Survey or Canada's Dominion Land Survey and the survey points are marked on the maps, that might help a lot. My understanding is that here in North America, they don't move those even if they turn out to be in the wrong place.

Anyway, the project sounds like a lot more fun than most programming/computer stuff.

Some Inexpensive Methods for Digitizing (4, Informative)

eldavojohn (898314) | more than 4 years ago | (#31431526)

I'd suggest appealing to Google or the brothers that did tapestries for the Met [] . What are these maps of? Is there a society for the place that they cover where you could appeal for funds under the pretense that you publicly release the maps?

Assuming all those avenues are exhausted, let's look at some cheap and dirty DIY methods. I'm assuming you've got a MP digital camera. There are sub $100 ten megapixel cameras [] out there but don't get anything with a fancy digital zoom. Next you'll need mosaicking software [] or if you're into software, you can try your own implementation of the KLT algorithm [] .

First off, practice all of this on layed out newspapers while developing your preferred methodology.

Your cheapest and most haphazard option is going to be lay the maps flat on the floor and cut a length of string with a washer on it (two to three feet?). Try to use brightly diffused lighting so that is normalized in the mosaics with no shots of your shadow over the maps. Now this is backbreaking but hold the camera flat over the map with the string extended in front of it so you can keep the distance to the map consistent. Don't angle the camer as this will slightly distort that tile and hinder the mosaicking. Put plastic bags on your feet if you need to walk on the maps. Take a picture, move a few feet in a grid style, take another picture. Rinse, wash, repeat until you have images covering all of the map. Collect the images and put them on the computer and verify the mosiacking works before preparing the map for storage forever.

A better method would be similar but to construct a large wooden rectangular box with plexiglass as a top so that you can fit this structure over the largest of the maps. Then cut holes in the plexiglass so that you can set your camera at a plane level to the surface of the map into the plexiglass. You might want to put an adapter on your camer that allows the lens and flash to be free of obstruction. You could make the tiles more uniform and save your back some work but you need to build and buy the materials for the structure. I think this is more time consuming but your best bet and will allow you to gather more images with less distortion.

Above all, remember to save the original images! It's probable that later better algorithms will be developed to normalize the images, remove distortions, light problems, shadows and increase clarity on your overlapping sections. If you do the plexiglass route, you could manufacture it so that every bit of the map is photographed three or four times.

Not professional, not flawless but cheap and dirty. Hope this helps.

As for the geocoding, what are the maps of? You should actually check out the feature extraction of the KLT algorithm and consider using that methodology for syncing these up with maps. That will require human intervention though to identify the features, I'm sure.

Military use (0)

Anonymous Coward | more than 4 years ago | (#31431530)

I know that the US military has some large map scanners, so specialized equipment for this task does exist.

DIY? (0)

Anonymous Coward | more than 4 years ago | (#31431536)

Im going to suggest taking apart a flatbed and laying the map out on a large white surface. Then scanning the map in sections by hand, and digital stitching together the resulting image strips. This would probably be the cheapest and quickest solution (and then only you handle the maps so if something gets damaged, its no-one else's fault). As far as Geo-coding, im not familiar with anything along those lines, so your on your own... however "best guess" approach will probably be sufficient for projects needing moderate accuracy. You can probably find tutorials on taking apart scanners for similar use (not exact but this is DIY remember) over at they have some really interesting projects there, and iirc one that involved a disassembled scanner for one use or another. On any note, good luck with your project... wishing you success!

Hard to Do (4, Informative)

carp3_noct3m (1185697) | more than 4 years ago | (#31431540)

I actually have a strange fascination with old maps myself, and regularly crawl the web for all kinds of antique maps. One overwhelming commonality I have noticed is that even recent maps can often be wildly wrong. So for example, an 1600ish map of Europe will be so wildly inaccurate that you would only be able to pick one point on that map to apply geolocation specific coordinates, the rest would not match up. So, I know I didn't answer your question, but I just think that unless they are accurate maps, it would be a very hard challenge.

Re:Hard to Do (2, Insightful)

tbradshaw (569563) | more than 4 years ago | (#31431738)

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.

Re:Hard to Do (1, Interesting)

Anonymous Coward | more than 4 years ago | (#31431766)

Where the wrongness is a matter of scales, this can be handled by some deft stretching. You identify points - crossroads are good - by hand, and bend and spindle the scanned map accordingly. When a map is hilariously wrong this still gives more-or-less garbage, but even medieval maps often have the villages (or churches) in roughly the right layout, so stretch-correcting is useful.

The OpenStreetMap folks use this to pimp aerial photography and scanned old maps for use as base layers prior to tracing by mapping minions like me. Try the OSM-Talk mailing list as a point of contact:

Re:Hard to Do (1)

The_Wilschon (782534) | more than 4 years ago | (#31431768)

It might be interesting to see how many control points you would need to distort the maps (along a spline or something) and get quite close to accurate.

Re:Hard to Do (1, Insightful)

Anonymous Coward | more than 4 years ago | (#31431970)

Perhaps you could use morphing software to morph identifiable key points on the map to the same points on a modern map?

Re:Hard to Do (1)

martas (1439879) | more than 4 years ago | (#31431994)

one possible solution would be to find a set of potential reference points, and then apply some kind of transformation on the map so all the points match their true positions at once. would be a fun thing to look at. though you'd need some assumptions about the nature of error in maps, i.e. what sort of distortions did people draw with in the first place. and you'd either need experienced mapologists for that (yeah i know that's not a word), or tons of data.

Re:Hard to Do (1)

martas (1439879) | more than 4 years ago | (#31432010)

oh, right, cartographers....

University Libraries (0)

Anonymous Coward | more than 4 years ago | (#31431544)

I know that some University libraries are equipped to handle this kind of work. In particular, the Knight Library at the University of Oregon has a department dedicated to digitizing old works like this.

University cartography or geography department (4, Insightful)

molo (94384) | more than 4 years ago | (#31431566)

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: [] and their historical maps: []


Re:University cartography or geography department (1)

ClaytonianG (512706) | more than 4 years ago | (#31431740)

In addition to the cartography/geography department, some universities do this in a GIS department. GIS departments will likely be great sources for information on digitizing. Just read the bios of the professors in the departments and email the ones that sound like they would be interested. If the university is not interested in helping you, chances are you'll be able to find some cheap and high quality slave^H^H^H^H^H grad student labor to do this for you. Also check if your local university has a population/demographics center; they also tend to be interested in this type of data.. Old maps are of high value for historians as well.

Now if you are not wanting to share the contents of the maps, that might put a hiccup in this strategy.

Re:University cartography or geography department (1)

Lunatrik (1136121) | more than 4 years ago | (#31431842)

I second this - if you happen to live near Atlanta, GA Georgia State has a nice cartography / GIS lab. UGA used to as well. Most state colleges will have a geography program or GIS certificate, either way you go you should find people ready and willing to help!

I see what's going on here (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#31431568)

Let me guess, they are historical maps from the Revolutionary War, aren't they? Well, let me cut to the chase and give you the spoiler: WE WON. Your maps of British front lines and troop movements just serve to document how the British "empire" got its ass handed to it by a bunch of pilgrims and white wigged hippies. Pathetic. Burn them, you poofter.

Digital camera + HUGIN (0)

Anonymous Coward | more than 4 years ago | (#31431570)

It can do the orthorectification along with the blending and exposure compensation. You could even do it as an HDR to really preserve it!

UTM (0)

Anonymous Coward | more than 4 years ago | (#31431576)

The Universal Transverse Mercator (UTM) co-ordinate system will be the easiest to apply to your maps. I would start by researching "world files."

Your maps are probably wrong (0)

Anonymous Coward | more than 4 years ago | (#31431594)

Turns out a lot of pre-GPS maps are not that accurate [] .

Do you have lat/long? (1)

e2d2 (115622) | more than 4 years ago | (#31431618)

OP didn't mention if these maps have lat/long data in them. If so then you are good to go with using Google Earth and it's KML format to describe the map and it's inherit location on the globe using lat/long points of known locations or map end points.

If you do not have lat/long you may need to match up the map with an existing map using something like google earth and overlay it until it lines up properly. Then you can get the end points for the map and, again, use KML to describe where it should reside.

Re:Do you have lat/long? (1)

codegen (103601) | more than 4 years ago | (#31431850)

Lat/Long mapping is what he is probably after. The latitude of a particular location is not exactly fixed. It depends on the reference geode used. You can have three maps of the same location specify different latitudes. GPS, for example use WGS84, but many older maps in North America use NAD 27. Official Gov of Canada maps use CSRS. In fact better GPS units allow you to change the reference geode in the software to match the one on your map.

If you take a map with coordinates in WGS84 and try to align it with one of the older maps, you are going to be surprised.

As for the original question, the poster should look into giclee printing services. Giclee printing is a pigment based printing on art paper or canvas. Most Giclee printing services also offer laser scanning as well as a means of high quality prints of the original art.

Contact your local universities (2, Interesting)

RingDev (879105) | more than 4 years ago | (#31431634)

Really, history majors will love this stuff. Giving them maps and a concept of Google maps overlays for real time comparisons to modern maps will likely be a capstone project for some undergrad.

A few years ago while working for the State of Wisconsin's Board of Commissioners of Public Lands we worked with the University of Wisconsin: Madison to get all of the original land plat maps of the state digitized, indexed and search-able. Same type of deal, huge maps on really old paper that had to be vault kept with humidity and temperature controls.


Digicam? (2, Interesting)

natehoy (1608657) | more than 4 years ago | (#31431666)

Focus on the preservation of the imagery first, obviously, because once that's gone it's gone forever.

The cheapest option is a large-megapixel digicam known for good image quality. SLR would probably be a good bet. You can take multiple images and stitch them together without too much trouble, so you can get reasonably fine detail with a little work even with a $200 consumer camera. Or, alternatively, hire a professional photographer and have him/her take really high resolution photos of the maps. The advantage of this approach is that you don't have to take the maps anywhere or do anything special with them. Just lay them out on a low table or the floor and align a camera over them, and take heavily-overlapping shots.

Large-format scanners might cost some serious coin even to use for a one-time project like this, but would probably yield better results with less effort.

You might check with local companies that deal in maps and cartography, they might be able to recommend ways of saving the imagery, and some might even offer to help out if the maps may be of commercial interest (they might even share the proceeds with you in addition to giving you high-res digital images).

But I'd say if the maps are truly delicate, your first focus should be to take the highest-resolution images you can of them now, even if it's multiple images per map that need to be stitched. That way, you have *something* preserved in case one or more of the maps is destroyed or deteriorates further before you can preserve it.

If there are particularly interesting features of the map, use the MACRO feature on your camera - most stitching programs can integrate images at different scales and preserve a lot of detail. I used the "Hugin" pano toolkit (free) to stitch together about 100 random photos I took at the top of the Eiffel Tower into an impressive contiguous 360 panoramic shot, and it was literally a "here are the pictures, figure it out" process. The pictures were all taken at different zoom levels, different angles, and all sorts of issues, yet it looked like a Google Street View 360 image. This was 5 years ago, I can't imagine how much better the technology is today.

The geolocation shouldn't be all that hard - it's a matter of choosing a few points on the map and identifying their coordinates accurately. Of course, if there are few/no reference points it gets a lot harder. [] is a good starting point to a group that does free, open-source mapping. They or some of their related sites might possibly have a tool that does what you want. Also, a professional cartographer may be able to help you out as well.

Look to the professionals (1)

ultraexactzz (546422) | more than 4 years ago | (#31431682)

This'll sound stupid, but call your local municipal government. My city, for example, has a nice big scanner that works well for old and well-worn maps. They might even scan the maps for free, esp. if they can keep copies (if your maps include their jurisdiction). Your other option may be to contact a blue-print or architectural printer - even if they don't offer this sort of service, they may know someone in your area who can help.

Define 'Quite a few' (0)

Anonymous Coward | more than 4 years ago | (#31431698)

Quite a few = 30, or
Quite a few = 3000

Different approaches will make sense at different project scales.

We can help! (5, Informative)

Richard Fairhurst (900015) | more than 4 years ago | (#31431700)

First, ask on the OpenStreetMap mailing lists. There's lots of us who've done this kind of stuff before, and we'd be really pleased to help. I collected, scanned and rectified the Ordnance Survey's New Popular Edition - a complete set of England and Wales maps from the '50s, now out of copyright. It's all available in OpenStreetMap as a background layer and loads of people use it for adding rural roads, rivers, placenamese etc. Others are scanning other old Ordnance Survey series right now. Seriously, we love this kind of stuff. (#osm on OFTC can help too.)

Secondly, GDAL [] is definitely your friend. It's the most amazing set of command-line tools for rectifying and reprojecting data. gdalwarp and gdal_translate are probably the two you'll use most.

Metacarta (1)

Aurisor (932566) | more than 4 years ago | (#31431722)

I'd take a look at some of the projects at Metacarta labs ( I worked there for a couple years, and they do a lot with converting old maps into digital, interactive versions. If you get in touch with them, they have some super-enthusiastic people who can give you great advice.

DSLR camera & Google maps API (1)

Vandilzer (122962) | more than 4 years ago | (#31431726)

1. Digital SLR camera, pick your flavor, I like the Canon EOS 5D Mark II
2. Tripod to Stabilize the camera and allow for constant distances & angle (right angle) when shooting... Your going to want something with a center column so you can adjust the hight without adjusting the legs.
3. Some kind of ambient lighting to prevent shadows and so you can shoot at a low ISO (less noise) and a high f-stop
4. Stitching software like this: (If you are are using the tripod and keeping a constant distance any photo program should do.

Put map on a surface, take many photos, stitch, takes some time for the first one but it will be quick once you get going.

Old maps and geo coordinates...maybe a Google maps or earth API like this:

Use survey markers (1)

Kreuzfeld (308371) | more than 4 years ago | (#31431736)

What type of maps are these?

Many professional-style maps in the USA -- e.g. quad sheets, parcel/tract maps, etc. -- will have survey markers indicated. Ideally these would be set benchmark disks with longitude/latitude noted. Many maps also mark boundaries of townships, sections, and half- and quarter-sections, locations of which should be available from the local municipal authorities.

These sort of well-defined points are probably your best bet for empirical location, but if your maps are 100 years old the coordinates may not be precise enough for digital overlays. In the end, you may well be forced to manually align your maps with something more modern.

There are scanning services... (1)

sgage (109086) | more than 4 years ago | (#31431748)

... that can handle just about anything. I had a very large historical map/timeline (maybe 1m x 2m) scanned by a professional service, and they did a very good job. This was years ago. I would think you could find someone in your part of the world to do it.

I also posted here to say that I think your project is a very worthy one. Good luck!

Google Them (3, Funny)

imscarr (246204) | more than 4 years ago | (#31431770)

Take photographs of them and put them on the internet. Google will automagically index them and add them to their street maps in real time.

GeoTIFF and (1)

agbinfo (186523) | more than 4 years ago | (#31431776)

Google for GeoTIFF and spend some time here []

Easy enough (1)

hyades1 (1149581) | more than 4 years ago | (#31431790)

Buy or borrow a high-end DSLR. Lay your maps out and provide good lighting (avoid using the flash). Because the images you produce will contain a lot of hard lines, any decent panorama software will stitch them together beautifully. I recommend Hugin, which is free. PhotoShop CS2 or better, if you have it, also does a really good job.

Feel free to send me a copy. I love old maps.

Camera lense distortion (1)

vcgodinich (1172985) | more than 4 years ago | (#31431798)

I don't know if anyone has actually tried to do what the majority of people seem to be recommending on here, but it doesn't really work.

Up close any camera will have significant distortion, way less resolution, and be much harder to control in terms of lighting / contrast / brightness.

It might sound good and easy, but for anything archival it is such a bad idea. been there, tried that, went back to a scanner solution.

Sheet Feed Scanner is the key. (0)

Anonymous Coward | more than 4 years ago | (#31431804)

Find a location that has a sheet feed scanner, put your map inside a scanning sleeve, then put it through the machine. Depending on the size of the scanner, you can scan practically anything flat.

I scanned 100+ historical maps this way during my summer internship at WVU for the library. I used Photoshop to bring them in, then exported as a .tif. You can use the .tif along with ArcMap to georeference the figures to an aerial image.

Cruse Scanner (0)

Anonymous Coward | more than 4 years ago | (#31431812)

Large format scanning (not just taking digital photos) - you have two options...
1) Any drafting reprographics place should have a feeder style scanner that can duplicate blueprints, posters, etc. But this method is not great for fragile source material.
2) My company has blueprint scanners, and one of these:
The bed moves under the lens allowing a 150 megapixel 2D scan of a 3D object. We have scanned lots of artwork and antique maps on this machine.
Once you have a digital image you can make this into a GPSr map file. Tutorial here:
Sounds like an interesting project... Good luck!
PS - I have to agree with earlier poster - lack of accuracy on the original map will skew your geolocation coordinates... Assign as many know geocoordinates as possible to you images.

QGIS or ArcGIS for georeferencing (2, Informative)

spandex_panda (1168381) | more than 4 years ago | (#31431820)

Hi there, I am a spatial guy so thought my 0.02 may be worth something. I am not too sure about digitising them, maybe a print shop or as suggested in other posts you could talk to your local university geography department or a government mapping agency

Once they are digital though you need to georeference them. As mentioned in the title of my post, it is easiest to use GIS to do this and you can use QGIS with relative ease. Install it using osgeo4w [] on windows or the ubuntu ppa for qgis [] . Alternatively if you have a license then use ArcGIS. If you have a map of the underlying roads for the maps you are digitising then what you do is find points on the roads and match them to points on the scanned images, this provides data for a transformation and will shift the map onto your coordinates.

cruzcam (1)

MadCow42 (243108) | more than 4 years ago | (#31431828)

Find a service provider or museum with a digital Cruzcam. They are a copy stand with an integrated camera/scanner system meant for exactly what you need.


Lots of work required...believe me, I know (2, Interesting)

TimmyDee (713324) | more than 4 years ago | (#31431846)

I spent a summer doing this in grad school for the Vegetation Type Mapper [] project at UC Berkeley. I'm not going to lie to you--it was a ton of work. But the results were cool. The site has all the old maps georeferenced, plus ways to download them.

Needless to say, the library was involved in the project, as was a giant scanner. We relied on ERDAS Imagine software to georeference the old maps to current USGS base maps. There was also a lot of accuracy assessment involved to make sure we minimized error in the georeferencing process. Probably one of the trickiest parts was making sure the old landmark you were using as a control point had not substantially changed in the intervening decades.

My professor and her colleagues published a paper detailing the project [] .

if you are in the UK (0)

Anonymous Coward | more than 4 years ago | (#31431864)

you could try companies which sell historical mapping e.g. landmark group their business is based on historical mapping and georeferencing and they may even be interested in paying for the data if they can resell it?

Geocoding (5, Informative)

spasm (79260) | more than 4 years ago | (#31431866)

Others seem to be describing some good solutions to getting the map scanned, so here's how to geocode and rectify the image using the open source Grass GIS software:

Step 0:

- You need to have a location already created in grass, with some contemporary data in it (physical features, roads etc where there's some concurrence with the map you're trying to geocode). The projection you've used doesn't matter much - a later step is going to be rectifying (ie distorting) the scanned map to match the projection of the digital map. The created location does need be at least as large as the scanned map (ie if the map is everything in a 5 km radius of some town, the grass location also needs to encompass at least a 5 km radius of the same town).

Step 1:

- Come up with a list of features/points which exist on both maps. Depending on the scale of the map, this could be intersections of specific roads, locations of towns, peaks of mountains etc. You're going to need an absolute minimum of five points for the rectification process to have any chance of working; more than fifteen is much better. Try and select points which are unlikely to have moved over time (coastline or river features for example). In grass, mouse over each point and record the coordinates.

Step 2: import the scan

In grass, do: input=[path to scanned file] out=[Mapname] location=templocation

Quit grass

Step 3: target, point, rectify

Open grass, but this time in the 'templocation' you created in step 2 group=groupMapname location=[modern map location name] mapset=PERMANENT group=groupMapname in=Mapname
d.mon start=x0
i.points groupMapname

d.mon will open a window; i.points will display the scan in it. Select the mapname in the dialog that appears, then one by one select each of the points you've identified as having concurrence with the modern map. In the terminal window, enter the coordinates for the point taken from the list you created in step 1. When done marking points, click 'quit'.

i.rectify -a group=groupMapname extension=_1 order=1

Depending on the size of your map and your processor speed, this bit may take a while. When done, quit grass.

Step 4: admire output

Open grass in the modern location. The scanned map will be available as a raster layer for display. The scan will have been rectified so the map matches the projection of the modern map layers - ie you'll be able to see what's moved and changed, and what exists now that didn't then etc. There's other grass commands which will help you convert features of interest (rivers, roads, contour lines, whatever) into vectors if you really want.

If all this seems too hard, have a look at qgis - also open source mapping software; it's more gui-oriented and I know it has a georectifying plugin. I've just never used it.

Good luck.

treasure map? (0)

Anonymous Coward | more than 4 years ago | (#31431872)

Is this possibly a treasure map? is that why you need to overlay it? I want in.

Laqrge-format scanner (1)

brindafella (702231) | more than 4 years ago | (#31431898)

There are a few makers of large-format scanners. Océ is one. []

These are not cheap, or common. They are likely found in places where maps, charts, technical drawings, or similar are printed on large-format printers. I would be asking friends who work in government offices or land-planning areas whether they have a large-format printer (and an associated scanner) somewhere, and then see about arranging a "side-job" out of business hours.

The scanned images are quite large, so expect to also bring several CDs or DVDs to transfer the files.

Use a digital camera (0)

Anonymous Coward | more than 4 years ago | (#31431902)

If you do the math, a 1.5m x 1.5m map at 100dpi (screen quality) [] is only ~34,810,000 pixels. You can capture 40 million pixels with a modern medium-format digital camera [] . Of course, there is no requirement that you use a single photo. With a good tripod and a typical 'point-n-shoot' or DSLR camera, you can stitch multiple photos into a single high-resolution mosaic [] .

Read up on how David Rumsey's doing it ... (2, Informative)

timothy (36799) | more than 4 years ago | (#31431922)

Saw a great presentation at OSCON a few years back about the massive digitzation effort undertaken by David Rumsey ( See [] -- Drew a well-deserved standing ovation.

In the course of the talk, I think he said that he'd scanned the first 10,000 maps (though even 1,000 sounds ridiculous -- maybe it was 1,000) before hiring assistance.

Of course, he had more money to play with, so he probably had a pretty big scanner ;)


Location, Location (1)

esme (17526) | more than 4 years ago | (#31431932)

Several people have mentioned good resources (museums, local government, geography dept., etc.). I'd add university libraries to that list (especially the maps or special collections departments). But the most important thing is location. Since you don't want to move the maps more than necessary, and if the maps are of your local area, then the library/museum/government in your area will be most interested in them.

For geocoding the maps, I think you'll need to figure out what you're going to do with them. If you want to do overlays in Google Earth, then using KML will probably be the best. If you want to use some other GIS software, then whatever formats it accepts, etc.

Use panoramic stitching / Gigapixel technology. (1, Informative)

Anonymous Coward | more than 4 years ago | (#31431936)

Hi, I'm a panoramic photographer, (I have shot panoramas up to 18 gigapixels in size, which currently seems to be a world record) so I hopefully am speaking from experience. What you want to do is basically shoot a panoramic image of your map.

You should situate your map as flat as possible, and shoot photos of it from a perpendicular point of view - best to hang it on a wall I guess. In the case of a very fragile map, sure, you can lay it on the floor. Take care to light it evenly.

You can then use PTGui (my favorite panoramic stitching software by far - only a satisfied customer talking) to stitch the images together into one perfectly seamless image.

Some key things to remember are to keep the map as flat as possible. A long lens is probably better, but you can use a macro lens also.

PTGui has a very handy feature called "viewpoint correction" which can join different images *of a flat surface* together, even if you didn't shoot these images from the same point (this is useful for panoramic photography when we want to capture the area below the tripod). In the case of shooting your maps, this will be very handy indeed.

Feel free to contact me via my website's contact form (360 cities dot net) and I can help advise further if you want.

good luck,
Jeffrey Martin

Quick post since I am heading out (5, Informative)

anlprb (130123) | more than 4 years ago | (#31431976)

Contact a local Licensed Land Surveyor. We are in the business of coordinating maps and making sure they are properly referenced. We also know the difference between NAD83 and NGVD29. This and the other coordinate system conversions and the proper use of scale factor in SPCS (State Plane Coordinate Systems) is something we do every day. Plus, most of us are really into local history and could possibly show you some other really neat uses for that data. Historic societies are always looking for ways to map past events. When speaking with a Surveyor, we can usually know what the practice for a given time period was. There are three different lengths for a foot that I have come across working. International Foot (not used in surveying, but sometimes engineers use the wrong foot), US Survey Foot (standard) and the Philly Foot. Philadelphia has a different set of standards for how a long a foot is, depending on what part of the city you are in and what you are trying to do. This is not something most historians would accurately pick up. Surveyors will. We also know who was the good and not so studious Surveyors in the area and what tricks each used to mark corners, turning points and reference markers. A local Surveyor in the area the map is of would be very interested in helping you with your work. He/she may have already done the heavy lifting for you. We have to trace maps back as far as possible, so sometimes (I am in New Jersey) we have to go all the way back to the Proprietors to get maps so that we can run lines that control our current work.

Long story short, if it deals with cartography or local surveying, seek a professional Surveyor.

A similar problem described in the New Yorker (1)

Univac_1004 (643570) | more than 4 years ago | (#31432006)

Two or three years ago the New Yorker ran an article about digitizing a large tapestry. As I remember the tapestry was laid out on a floor, and a high-resolution scanner was moved over it on a framework of some sort.

This took a while (days or weeks) and the fabric, responding to changes in temperature and moisture, would slightly moved between the times when different sections were digitized. Reconstructing the original appearance of the tapestry in the digitization became quite a problem

This seems to resemble your problem in several aspects.

The article describes how two mathematicians solved the problem.

Though it concentrated more on the human side of the issue than the technical, it still contained a few hints as to how they did it.

I'd suggest reading that article to see what you can glean. At the very least it can provide with some names to use either for a literature search or to contact directly.

A hint is that the tapestry featured a unicorn, and that word was probably in the title of the article.

If you have trouble locating it, try writing me.

Ask David Rumsey (0)

Anonymous Coward | more than 4 years ago | (#31432152)

I heard David Rumsey speak at the Long Now Foundation. He has a large collection of historical maps and wanted the ability to share his library with a broader community. He decided to digitize them and make them available to the public. He has also done work with geo-coding old maps and overlaying them current maps to either highlight changes in topography or errors in original map making. It sounds like his efforts encompass what you're trying to achieve.

I'd suggest reaching out to him or his organization to find out how they do their work... or maybe they can help.

I've done this (4, Informative)

sidb (530400) | more than 4 years ago | (#31432162)

I have done this for a grant-funded historical map digitization project at a university library. We used a $40k large-format scanner (from Betterlight) which can scan the whole item laid out flat. Trying to stitch together camera images will result in distortion across the image—if you didn't need to distort it, you wouldn't need special software to do it; you could just line the pictures up.

But even once you have image files, there's about zero chance you can just replace Google Maps' tiles with your own and expect geotagged stuff to line up where it should. If you have a finite number of places of interest, you could manually locate them on each map and then try to distort each map to align, but if you expect arbitrary geolocations to need to be right, give up. Non-satellite/GPS-based maps are examples of practical cartography, not theoretical. They will be even less perfect than you think, no matter how professional they appear. Or do what we did: keep the geotag display on Google's maps, but show your historical map of the same general region side-by-side and allow the user to calculate the precise correlation in his own brain.

Library of Congress (1)

BoRegardless (721219) | more than 4 years ago | (#31432254)

I've listened to the person in charge of archiving at the Library of Congress who handles such things, as do many other libraries. They have developed a lot of techniques for handling and dealing with large items, including restoration. I'll bet the British Museum has a similar map department.

My bet is they have information on this at their website.

Grass GIS Georectification (1)

guyfawkes-11-5 (1583613) | more than 4 years ago | (#31432256)

I dont know if this has been mentioned but Grass GIS the open source GIS program , has a georectification module that you can use to add the proper coordinates. Here is a page of the manual for your perusal. []

The Mannahatta Project (1)

Locke2005 (849178) | more than 4 years ago | (#31432348)

National Geographic did an article on The Mannahatta Project [] , which did the same thing -- digitized old maps, then matched up known reference points to map them into modern map overlays with GPS coordinates. It also provides some background on why this is such a cool thing to do.
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