Global Mapper v25.0

Problems Exporting ASTER Data

andrew.lam
andrew.lam Global Mapper User
edited June 2011 in Elevation Data
Hi,

I'm trying to export ASTER in any type of raster format.

I've been able to import and merge the ASTER data using GM's online download function. However, when I export the data as a GeoTIFF or USGS DEM the data is segmented.

I've attached screen shots of the original and exported data and also attached a zipped copy of the exported USGS DEM data.

Comments

  • global_mapper
    global_mapper Administrator
    edited June 2011
    It looks like there are tiles missing which is not uncommon with that server, it is often flaky and fails to deliver some tiles. If you retry the same export then those tiles might successfully download this time, filling in more of the holes. After a few retries hopefully everything is filled in.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • andrew.lam
    andrew.lam Global Mapper User
    edited June 2011
    Thanks for the tip.

    I don't mind waiting a bit longer for GM to download data from the server to get a complete export image.

    Is there a way to ensure the data is fully downloaded before attempting to export?

    Thanks,
    Andrew
  • global_mapper
    global_mapper Administrator
    edited June 2011
    Andrew,

    Currently the operation will retry the same tile 3 times before moving on and assuming there is a problem with that tile. Unfortunately if the server goes offline for a brief period of time (say a couple of minutes) this would make that tile fail to download enough times to give up, otherwise exports can get stuck forever if a server is down for a while or has problems with some tiles. I'm not sure of a good solution for this for servers that aren't reliable.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com