Contribute to the NYPL Map Warper Project
The New York Public Library offers a lot of very interesting digital projects. Map Warper is one of their interesting forays into crowd sourcing. With this tool, participants can contribute to NYPL’s ongoing efforts to overlay their historical maps on top of a current map of New York.
After creating an account on Map Warper, you can search through their database of maps taken from their collection of 400,000 historical maps. You can either search by keyword for specific types of maps or you can browse through all of the maps to pick one that interests you. Once you have selected a map, you can start the process of “rectifying” or aligning the map with a current map of New York. As soon as you have zoomed in on the proper section of the current map of New York, you can start setting Control Points. To do this, you identify the same point on each map and drop a pin at that location. As you set each control point, you will see a calculation below estimating the amount of error between the two points. As long as that value remains below 10, your Control Points are acceptable. Once you have identified a minimum of 3 Control Points, you can move on to cropping this map. This stage lets you remove any decorative border or other extraneous information. Cropped maps can then be aligned with the current map of New York. After that process is complete, you will see the the historic map you worked on layered over the current map of New York. You can then use the sliding bar below the maps to change the opacity of the historic map to see how well aligned the two maps are and to check out how New York has changed since the time when the historic map was created. If you are interested in the history of New York or historic maps in general, the process is fascinating. Rectifying maps also offers a nice sense of having contributed to NYPL’s database of historic maps. The project is a great example of crowd sourcing used well. As an added bonus, last week NYPL announced that 20,000 of the maps included in Map Warper are now available for high resolution download and use under a Creative Commons CC0 1.0 Universal Public Domain Dedication, making them available for use in all sorts of other projects. Whether you want to contribute to the project or just need to find a historic map you can use in another context, Map Warper is definitely worth checking out. You can see Map Warper in action in the YouTube video below.