Reflective Blog Post – Georectifying

Georectifying with oldmapsonline.com is much more fun than I originally thought! The process of telling the computer which points need to be aligned where is so simple, yet by doing so just a few times, we can correctly overlay an older image of a map to a modern one! It distorts the image very well while keeping the relative shapes of each landmass, and it can even guess with decent accuracy for parts of the map without reference points. The way I see it, this has a lot of potential in DH, especially when studying the impacts people have on a landscape over time, in that vein, the development of cities and changes that follow such as levels of forestation and changes in nearby waterways lend themselves well to processes like this. The visualization and layering allow you to compare these developments efficiently and in an easily understood manner.

The map I worked on was entitled No. 46. Vorderasien und Agypten. When we started I was a little overwhelmed looking at the older map and trying to figure out not only how to read it, but how in the world I was going to find reference points to get a good overlay for the maps. The strategy I ended up using was looking for sharper angles around the edges of the landmasses on the maps, which worked out very well! This helped me understand how efficient the process of making and studying a spatial DH project can be. I notice that the map is available in the IIIF format, which we have already seen to be very helpful when creating omega items, for example. This format makes the image much more accessible in online archives due to the more consistent high quality.

The possibilities for a georectified map that I see are mainly in environmental and humanistic studies looking at changes in these landmasses over time, the development of the land, things like the spread of agriculture and cities, and things of that nature. Essentially the main area of potential I recognize here is tracing the impacts of human activity using multiple layers of maps. I could see creating a timeline to show when specific changes took place as a helpful next step if that is the direction being taken with your research. Having a timeline, especially one with a scrubber, would allow users to interact with the map and take note of more individual changes. I can see this being done by overlaying multiple transparent maps chronologically and having maps become more opaque over time to show those changes. Possible issues that could arise are different map styles being ungeorectifiable because they aren’t created from the top-down viewpoint that we are used to. For example, traditional Japanese maps aren’t top-down but rather take the perspective that one may see from a point far away. They include land formations like mountains and have much more depth than European or Western maps. Finally. though it is incredibly useful for more geographical questions, I don’t believe that this method would be helpful when researching the reasons behind certain changes beyond that. The scale of the projects as well as the fact that georectifying doesn’t say much about what was happening with the land itself, though you can make great inferences using the way borders are drawn/redrawn, names of locations, and evidence of human activity.