|Abstract||Colour orthophotography of the Cocos (Keeling) Islands, derived from aerial photography taken over the islands on 5th April 1987 (islands only, not including the lagoon). The orthophotography has a 25cm on-the-ground pixel size. The quality of the orthophotography is impressive, with acceptable resolution down to 1:400 scale.|
|Search Word(s)||PHOTOGRAPHY AND IMAGERY Aerial
PHOTOGRAPHY AND IMAGERY Orthophotography
|Geographic Extent Name(s)||Cocos (Keeling) Islands Edition 1 2010 1:25000 - Geoscience Australia GEOCAT 70146|
|Maintenance and Update Frequency||as required|
|Stored Data Format||DIGITAL - ERMapper ERS & TIFF/TFW|
|Available Format Type||DIGITAL - ERMapper ERS & TIFF/TFW|
|Access Constraint||See contact details below.|
photography was flown by Australian Survey Office Canberra in 1987,
scanning was done by Kevron Aerial Surveys and orthorectification by
LandInfo (Canberra) in 2000.
In December 2003 GA projected the data to UTM (WGS84) zone 47S.
In February 2005 GA reporjected the imagery as a whole and re-cut the tiff imagery to improve visualisation of data.
|Positional Accuracy||GA expects the Cocos orthophotography over
the main atoll to be within a meter of its true position.
Exceptions to this high level of accuracy are Horsborough Island and North Keeling Island, which are on unconnected flight lines and did not have reliable ground control available. Initial indications are that the North Keeling orthophotography could be around 35 meters out, and the Horsborough Island orthophotography could be up to 20 meters out.
|Attribute Accuracy||not applicable|
|Logical Consistency||not applicable|
|Completeness||Appears complete for all areas. Georeferencing of Horsburgh and North Keeling Islands has not proven to be very accurate.|
|Contact Organisation||Attorney-General's Department|
|Mail Address||GPO Box 594, Canberra, A.C.T 2601|
|Locality||111 Alinga St, Canberra|
|Telephone||(02) 6249 9479|
|Facsimile||(02) 6274 8040|
|Electronic Mail Address||Keith.Porrit@ga.gov.au|
|Projection||UTM (WGS84) zone 47S|