In 2011 AAM was commissioned by the Commonwealth to fly an airborne laser scanning survey of Christmas Island. The provided 1km by 1km ESRI grids were stitched together using ESRI ArcMap 10 to form 2km by 2km tiles. In some cases the tiles are 3km by 2km to accomodate DEM grids with less than approximately 30% land cover. Using the software program ER Mapper 7.1, a wet look shiny colour drape algorthim and a HSI algorithm were applied to each of the 48 tiles.The colour range has been optimized for each individual tile to provide maximum information and clarity of features such as slopes, depressions, hills, cliffs and mining relics. A consequence of this is that colours may not match at adjoining edges. The resulting images were saved as compressed ecw format.
The positional accuracy is the same as the accuracy of the 2011 digital elevation model. As a guide, the DEM data is vertically accurate to 15cm and horizontally accurate to 30cm.
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