Aerial photos are another type of raster data. Such data are used effectively as a background to enhance vector maps. As mentioned, the cadastral base for the DOL produced a vector land parcel map. Overlaying it on an ortho image (rectified photomap) enables the visualization of the relationship between the parcels and the surrounding geography. In 1996, the BMA obtained a new set of aerial photographs to support planning and related activities, however they are yet to be used for security reasons. They also plan to use less expensive small format (4 3 4 in.) aerial photography to produce and update maps. Again the BMA has had this technology for many years but to date it has not been able to use it owing to internal reasons including delays in gaining approvals to take photographs for security reasons