ConceptStation - level of accuracy between USGS low, medium and high level terrain data from Geocoordination services

Hello,

I am looking to verify the accuracy of the various resolution options (low, medium and high) for the terrain data that ConceptStation can import from it's geocoordination services (within the US).

From what I understand, the data is pulled from from USGS. Does geocoordination services filter terrain data between each resolution option (low, medium, and high) at a set percentage and if so what is that value used? If not, what is the quantifiable differentiating factor between each resolution status?

Also, is there information available on the overall level of accuracy of the terrain imported from USGS and any specifics on how that data was collected?

Thank you,

Marc

  • Hello Marc,

    Geocoordination Services (GCS) is a spatial index that returns datasources for imagery and terrain according to the LAT/LONG polygon that the application provides. For North America, its primary sources are USGS and GeoGratis.

    From the list of terrain datasources returned by GCS, Conceptstation groups the results into 3 different buckets, low/medium/high resolution, assuring that each bucket has 100% coverage for the area supplied.

    You can inspect each bucket by selecting it in the dialog and clicking on the 'I' icon in the Details column. This brings you to the 'Selected dataset details' windows where it lists each file and its Term of use.

    Typically for the USA, the results will be:

    High:   1/9 arc-second (3.4m of resolution)

    Medium:  1/3 arc-second (10m of resolution)

    Low: 1 arc-second (30m of resolution)

    I hope this helps,

    Simon

    Answer Verified By: Simon Normand