Google's Latitude & Longitude vs VT locations

Tips for creating and manipulating planet textures for Celestia.
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selden
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Google's Latitude & Longitude vs VT locations

Post #1by selden » 27.07.2007, 04:20

Has anyone placed objects using the latitude and longitude shown by GoogleEarth and compared their positions to what is shown by high-resolution VTs?

I'm seeing a discrepancy: using values shown by GoogleEarth, LongLat is placing the VAB and LaunchPad 39A significantly to the NorthEast of their locations on VT images of Cape Canaveral.

I don't know if it's a problem with GoogleEarth, with LongLat or with the placement of the VT that I'm using. (Perhaps a fence-post error?)
Selden

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selden
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Post #2by selden » 27.07.2007, 14:07

To verify that it wasn't only the Cape Canaveral Addon, I also did a comparison with the location of Andrea's VT of Venezia (Venice, Italy). Something's wrong there, too.

Here's a picture of the offset for the VAB. It should be placed just below the dark blotch (the building's shadow) in the center. Instead it's offset toward the north-east.
Image

Here's a picture of the offset for Venezia. The location marker should be near the grey industrial area. Instead its down south in the residential section:
Image
Selden

mk
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Post #3by mk » 28.07.2007, 17:44

GE images are not always properly georeferenced (sometimes the imagery is shifted by many, many metres).
You should also try using coordinates given by World Wind or Virtual Earth - so you'll know if it's GE or Celestia VT fault.
mk


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