File talk:Easter Island map-fr.svg

From Wikimedia Commons, the free media repository
Jump to navigation Jump to search

Release note about the new version of the map (October 2008)[edit]

  • The map was drawn using available public domain data:
    • For the shorelines and additional data: Landsat 7 ETM+ high definition imagery (14,5 m precision)
    • For the topography: NASA Shuttle Radar Topography Mission (SRTM3v2), with shaded relief to ease the reading of the relief. The precision seems to be of the same level that the former sources used which were drawn by hand.
  • The choice of the references maps for the toponymy was improved resulting in several corrections in the spellings. There are also additional labels and the distinction between the ahus and the sites with moais which weren't ceremonial platforms is better made. Their position is also more accurate.
  • Bathymetry: This information isn't displayed anymore because I'm not sure the former source map is free. Furthermore, comparing this map to high definition multi beam grids points out that the data don't match so I don't think the printed map is reliable. Unfortunately, available multi beam data in friendly usable format only cover a very small part of the map and the NGDC ETOPO1 data has a precision (1,900 m) far too low compared to the SRTM3 one, so I thought it was better not showing it at all.

Sting (talk) 23:36, 21 October 2008 (UTC)[reply]

Retrieved from "https://commons.wikimedia.org/w/index.php?title=File_talk:Easter_Island_map-fr.svg&oldid=15419073"