As I am hoping to develop some skills in illustration for my thesis I decided to have a look for a something to do vector based drawings and distribution maps. The programmes I selected were ‘Inkscape’ and ‘Old Maps Online’. However for the benefit of the assignment I will be focusing on the mapping site for now.
I looked for a basic ‘mapping’ tool on DiRT website and while I’m ashamed to admit that I literally went for the first one I found, you’ll forgive me when I say it was entirely because it said “Old Maps” on it and I got a bit romantic about the whole affair. Fortunately the website it linked me to was by no means a let-down and was in fact a website I had used before to obtain an old map of Ireland for an interdepartmental assignment last semester.
The website is powered by Google Maps and allows you to zoom into a specific country using the ‘Map Rank Search’ window. Once you have selected your country, the right panel will display all maps relating to that area that have been generated from external archive sources. You then have the option to select the date range or search by entering textual parameters (Figure 1).
Once you have identified the map you would like georeferenced, select it and another page will open up. You can enhance this image as you see fit and once you have explored it you can then continue to the ‘Georeference this Map’ button. This will bring you to another interface that will outline the various stages in the georeferencing process.
According to instructions you need a minimum of 3 control points on each map to align the image. The more control points you add of course, the better. Control points are added to a known point or fixed location visible in both maps. A point is first added on the old map, then the modern map in the same relative location (Figure 3).
This will ensure adequate coverage and alignment. Once you have completed this process you can select ‘Clip’ to outline the older map version you wish to overlay. This will bring you to another interface with an explanation as to how to achieve this. Once you have clipped and saved your image you will be brought back to the world map view and the newly overlaid map will be visible (Figure 4).
You can zoom into this and alter the opacity to see if it aligns correctly (Figure 5).
If it does not you have the option of going back and altering the control points so it syncs up better. Remember of course that in mapping like this there is marginal room for error as the earths surface is not flat and is inherently curved. Many standard maps may not account for this so some distortion is to be expected. As you can see above the alignment wasn’t perfect first time around because I only selected three reference points, two of which were in the southern extent of the country and one in the north-east leaving the west completely out of alignment (Figure 6).
So to adjust, simply go back to “Georeference” and start adding more points.The next stage looks a lot better but you get the idea. The more reference points the better the alignment. So keep at it!
The website is generally well laid out however the front page is quite muddled and could be streamlined a little more effectively. Everything you need to know however about the website and its current ‘Georeferencing’ initiative is right where you would expect it. Another problem encountered was the number of separate tabs that are opened from start to finish. It would be easier and would make the whole process a lot cleaner if it just linked upon selection.
What I did like however is that you get the opportunity to georeference any map generated by the website by selecting the “Random” application. The one let down of this is that once you have been given a random map you aren’t linked to the area on the right panel (modern map). You are simply provided with a map and must find the area yourself based on the old map title in a lot of cases. Not a huge issue I understand but this seems a bit counter-intuitive on a site that generates entire map selections once you hover a box over a country at random. It seems like something that would just have made sense to synchronise.
Further to this when i went back through the DiRT interface i get linked straight to the map selection pane instead of the Rumsey page with all of the explanations. I’m assuming this is something to do with my having loaded a profile and started the mapping process already but that seems equally bizarre. I will try back again about this at a later date.
Anyway aside from all that it’s a wonderful website and example of crowdsourcing so I highly recommend getting on board. Ireland’s contributions are few when compared with the rest of Europe and we can’t be having that so get to georeferencing and have fun doing it 🙂
Not wishing to forget entirely about Inkscape (which is a open source version of Adobe Illustrator) I added the product to the DiRT directory for future reference. Illustrator is a tool designed for vector based drawing and can be used in Archaeology (like AutoCAD) to produce profile and plan drawings of archaeological contexts, and can be used to create blueprints and graphics for company logos etc. I have number of friends who work in graphic design that assure me of its capabilities, saying that after 8 years of working with it, there are still features they are only just discovering. A very exciting prospect but I only need some line drawings.
I will be assessing how user friendly it actually is by drawing a floor plan of the Triskel Christchurch crypt and a Gantt chart that I need for a funding application.
Research Parameters for Assignment 1, DH6010