GeoTIFF elevation range

juddpattersonjuddpatterson Global Mapper UserPosts: 5
edited November 2008 in Elevation Data
I frequently import various elevation formats into GlobalMapper and export 32-bit floating point elevation GeoTIFFs that we use in ArcGIS. It is frustrating to me that all of these GeoTIFFs show up as completely black rectangles when initially brought into ArcMap (or previewed in ArcCatalog). The reason seems to be that the detected value range is 3.40282e+038 to 1.17549e-038 for all 32-bit elevation GeoTIFFs created by GlobalMapper. I see a value range of 32767 to -32768 for 16-bit elevation GeoTIFFs.

I have used many GeoTIFFs that show the correct value range in ArcCatalog and ArcGIS and are consequently much easier to use. Is there perhaps a little metadata tag that GlobalMapper fails to write that creates this issue? Thank you for any help!

Comments

  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited November 2008
    What version of Global Mapper are you using? Global Mapper should be writing out the elevation range in the file being output to the appropriate tags, either TIFFTAG_SMINSAMPLEVALUE and TIFFTAG_SMAXSAMPLEVALUE for 32-bit floating point vertical GeoTIFF files or TIFFTAG_MINSAMPLEVALUE and TIFFTAG_MAXSAMPLEVALUE for 16-bit elevation vertical GeoTIFF files. There were some older versions of Global Mapper that didn't write out these fields though. Perhaps that is the issue?

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • juddpattersonjuddpatterson Global Mapper User Posts: 5
    edited November 2008
    Thanks for your reply Mike! I convinced our office to buy GlobalMapper 9.03 back in late July 2008...I guess we just missed out on v10. Do you know if v9 should be writing those tags?
  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited November 2008
    Those tags should be written by any v9 release as well. Can you perhaps send me a vertical GeoTIFF that ArcGIS brings in with the correct range initially so that I can take a look?

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
Sign In or Register to comment.