A digital scholarly edition: Digital mapping

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In this blogs previous article, posted on the 20th March, a single semester module was discussed which incorporated practical Digital Humanities research under the supervision of an academic institution; yet which was essentially an individual project allowing this student to take full ownership of the projects development and workload. In contrast to that module, Digital Scholarly Editing is a module of two parts, running over two semesters, developing into a group-work project aiming to produce a finished product in the form of a digital scholarly edition.

TECHNICAL DEVELOPMENT

The first semester of this module examined many technical aspects which could be incorporated into the production of a digital scholarly edition.

Methods and tools relating to the encoding of a DSE such as XML, XSLT, HTML, CSS, metadata and the Text Encoding Initiative (TEI), were examined along with platforms used to host the same, such as Omeka and WordPress.

Practical workshops relating to the technical methods and theory behind the digitisation and presentation of primary source documents were held at An Forsa Feasa in Maynooth, and the National Archives of Ireland. The workshops demonstrated the use and benefits of advanced digital imaging equipment and accessible software tools such as Photoshop and GIMP, elements of which are discussed further in an earlier post on this site.

We were also introduced to the primary source document that would become the subject of our second semester group project and the object around which many of the above technical aspects examined could be put into practice.

THE PROJECT

This object around which this project is constructed is the World War I diary of Albert Woodman, an Irish soldier from Dublin stationed in Dunkirk in 1918 with the Royal Engineers.

In the process of making a digital scholarly edition from this diary, which at the time of writing is still a work in progress, the class group with responsibility for this project have been able to utilise many of the technical aspects studied in semester one. Encoding of the diary has taken place using XML methods and editors, while guidelines set out in the Text Encoding Initiative (TEI) have been used across the board in text markup, annotations and named entities.

In making a digital scholarly edition of a fragile ninety seven year old paper diary, careful imaging has also played a big part, with the pages of the diary being digitised to a high standard at the Imaging Lab in An Foras Feasa. Responsible manipulation of the images such as cropping or realignment using imaging software also took place when required, so as to present them as well as possible without altering their simplicity in the digital format.

Yet in this diary Albert Woodman also included a great number of other material including personal photographs, drawings, newspaper articles, clippings and a significant number of maps, cut out of contemporary newspapers or other periodicals documenting news relating to the War around him. These materials were also digitised at An Foras Feasa, however as the diary was being put together the idea of using the maps in a more interactive way began to be discussed which led to the arrangement of a further workshop on the technical aspects of digital mapping by Martin Charlton of the National Centre for Geo-computation, also based at Maynooth University.

DIGITAL MAPPING WORKSHOP

In approaching Martin Charlton the group had hoped that more context could be added to the black and white maps taken from newspaper clippings by potentially overlaying them onto a modern digital map, allowing users of the digital scholarly edition to view the small and localised Woodman maps in the larger context of how they relate to Europe today and as a whole.

In the workshop led by Martin Charlton we were first given a brief introduction to geographical co-ordinates and the issues regarding the presentation of the earth, a spherical object, onto a flat surface, a process which is known as projection. It was explained that several of these projections exist which may produce differing outcomes. The most appropriate for the Woodman diary maps was identified as the ‘Lambert Azimuthal Equal Area projection’, which is a projection onto a flat surface (a plane) which touches the earth at 52N 10E.

The software used to proceed with the mapping was introduced as QGIS, an open source geographic information system (GIS) and it was vital to identify the projection method that had been chosen in QGIS, which is EPSG:3035.

DIGITAL MAPPING SAMPLE

Having chosen a map by which to follow on from the workshop, my next step was to crop the image (below) as required. As this was a sample, focused on the map but not wishing to lose any of the clipping, I limited this to removing the outer diary page using GIMP software.

090-June13-W

Having cropped accordingly, ground control points needed to be identified within the map. These are points visible on the map which can be identified by Easting and Northing co-ordinates that relate to the same point on a modern map, in this instance Google Maps.

Crop 090-June13-W

In the case of this sample four towns which form a solid block structure that may adjust the Woodman map to sit at an appropriate angle on Google maps were identified as Chantilly, Villers Cotterets, Meaux and Chateau Thierry. The Easting & Northing co-ordinates relating to these towns, or ground control points, were then found and noted for use in QGIS.

Proceeding to QGIS a series actions allow the user to upload the map, choose the ground control points and assign these geo co-ordinates to the points on the map. Further running of this information through QGIS adjusts the map from a front on view to its actual geographic position based on the projection and co-ordinates used. Once this is complete it is then possible to bring into the QGIS workspace, which is now displaying the map in its correct geographic position, a second map such as Google Maps to sit in the same position in the workspace.

The final action allows the user to overlay the Woodman map over Google Maps and fade the Woodman map. When all is complete the result is the ability to see that the Woodman map now sits exactly overlaid on a modern Google map image, with the fade function allowing the user to see that the towns from the Woodman map sit precisely as they should over the Google map.

Image 090 geo-ref

The above image shows the Woodman map clipping cropped to show just the map and the notes from the article. Using QGIS it was realigned slightly to its accurate geographical position, was overlaid on Google maps, and the chosen ground control points of the four towns mentioned above match exactly from the Woodman map to the Google map.

What this tool shows is how technical work on these analogue documents can allow a greater context to a simple paper map clipping, utilising digital tools and methods to place a historic document in a modern setting and allowing greater reference. The digital scholarly edition of the Woodman diary will utilise many technical aspects studied within this module and digital mapping has been identified also as another potential addition, as work on the diary as a digital scholarly edition continues.

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