The location of an OASIS record is fundamental to establishing workflows of the form. For example, it helps filter which HERs and Museums have access to the record. This page is flexible enough so that a user can record one, or multiple ‘sites’ that their project covers. A site can in theory be:
- A single point
- Multiple points
- A single polygon (extent of area)
- A small number of polygons (e.g. Distinct survey areas)
- A single defined geographic area (e.g. country or district)
In Scotland, users are strongly encouraged to locate their project using the upload
option (see below), and thereafter using a numeric grid reference for spatial
accuracy. Users only have the options for Locating a project using a boundary
file or Entering a grid reference.
In certain cases you may find that the upload facility rejects your file. This is normally as the geometries are simply too complex to upload and store in the database. In this case, there is a separate section on the Additional Info page called “Additional Spatial Data for Canmore”; this allows you to attach the file to the OASIS form so your data can still be inputted into the national record. To proceed through the OASIS form simply enter a grid reference (centroid).
In England, users other options for Locating a project using a boundary file or Entering a grid reference, plus options to either Choose an area by an inhabited place or road name (using a Lookup service), or Using a predefined boundary or English Districts and ceremonial counties.
In both countries it is recommended that:
- For large area surveys use the file upload or choose a predefined area (in England).
- For planning related work use file upload, or grid reference entry.
Locating a project using a boundary file:
This feature should be used to upload a boundary/extent that represents where your site is located. There are some important aspects of this feature:
- It is limited to the Shapefile, GeoJSON or KML formats only.
- The file must be zipped up prior to upload.
- The file must have a spatial reference: either the British National Grid (epsg 27700); the World Spherical Mercator (epsg 3857) or the World Geodetic System WGS84 (epsg 4326).
- If your file does not have a spatial reference set, the form will reject the upload and display a small error/alert message.
- The form only supports Polygons - and not lines. Please do not upload site plans or complicated files that contain polylines.
- For simplicity: a maximum of 5 polygons per shapefile is allowed. If your file has more polygons than this the form will reject the upload and display a small error/alert message. If you feel that you need to record more areas simply create another site and split your polygons up accordingly.
- Very complex polygons with 1000s of vertices may take longer to upload. In certain cases the form may reject examples rather than extend the upload session and slow the application. In these cases, it is strongly suggested that you simplify the polygon.
A video of how to use the shapefile upload is here https://vimeo.com/437155147
Entering a Grid reference:
The field for entering grid references is currently restricted to three forms of data entry:
- 8 figure NGR alphanumeric e.g. SZ64408740
- Any size of NGR numeric coordinate up to 800000, 1400000
- Decimal Latitude and Longitude eg: 60.809179581126166, -0.8273674104847758
A video of how to add a grid reference (and edit) is here https://vimeo.com/437159665
Named Places lookup
In England, there is an option to locate your project using a lookup of the OS OpenNames service. It is important to note that this searches only named inhabited places and road names only. It does not include geographic names such as ‘Lundy’. It returns a central grid reference for the name chosen.
This feature is useful for where you may not know the grid reference, and can help you locate your position on a map and then refine to a more accurate location. If you want to record your project location as a larger administrative entity such as County or District, then use the Predefined Administrative boundaries option.
A video of how to use the named places lookup is here https://vimeo.com/437153996
Predefined Administrative boundaries
In England, for larger thematic studies that cover particular districts or counties a user is encouraged to select from boundaries as defined by the OS. This is a simple alternative to uploading your own boundary. Multiple areas can be selected.
About the Map
Points and Polygons are displayed against OS background mapping. This is maintained by the ADS as an internal web service. The embedded map allows you to edit points and polygons in the map itself.
When using a name lookup, the application automatically generates a point at the centroid (effectively the mathematical middle of the larger area) as defined by the lookup service.
There is a small toolbar on the left-hand side of the map with a number of icons which allow you to create/edit/delete features. If you hover your mouse icon over a feature a title should appear explaining what each one is. Here are a few examples:
- You can use the little ‘Bin’ icon on the left hand toolbar to delete the default point, and then (most importantly) save, and then add your own point or polygon.
- You can use the edit function to move the point to a more accurate location. Remember to press the Save icon!
- You can use the Point and Polygon functions to add extra locales within a site: for example, you may use the grid reference to get you in the right place, but then decide you want to create a polygon in the map to denote the field/building you are working in.
The map is in the WGS84 projected coordinate system (EPSG3857). The various functions can handle data entry in the British National Grid (EPSG27700), WGS84 geodetic system (EPSG4326), and EPSG3857.
For each Site you have to record a name. If appropriate, you can also record a distinct site code; the sort of identifier used to distinguish areas. Site code is not for:
- A Project Code: this should be entered on the Activity page.
- HER codes: these should be entered on the Reviewers/Admin areas page.
- Grid references.
- National Identifiers (Scheduled Monument IDs or other national inventories).
- Museum/Archive Accession Ids.