20. Geographical Skills: Aerial Photographs, Charts, Graphs and Infographics Determining Direction on Aerial Photographs
Some vertical photographs include a north arrow (figure 3). In such cases, use compass directions when asked to identify the location of features.
N
North-west North North-east
West
Middle Centre
East
South-west 3. A vertical photograph showing direction If there is no north arrow on the aerial photograph, use the following steps to determine direction.
1 Correctly position the Ordnance Survey (OS) map so the north arrow symbol can be read correctly like in the image above.
2 Choose a dominant feature in the foreground of the aerial photograph, such as a church, bridge or beach.
3 Pick another dominant feature in the background of the photograph and use a pencil to join the two with a straight line.
4 Now locate both features you chose on the OS map and join them with a straight line. 5 Use the north arrow on the OS map to determine the direction.
This method can be used on vertical and oblique aerial photographs.