You are here: > ESRI Forums > arcgis desktop discussion forums > Thread Replies

ArcGIS Desktop Discussion Forums

ArcGIS Desktop - Projections, Projection Engine forum

Difference between Lat Long WGS84 and GCS_W...   Amy Ramsdell Jul 09, 2008
Re: Difference between Lat Long WGS84 and G...   Melita Kennedy Jul 09, 2008
Re: Difference between Lat Long WGS84 and G...   Amy Ramsdell Jul 10, 2008
Re: Difference between Lat Long WGS84 and G...   Michael Ross Sep 29, 2009
Report Inappropriate Content • Top • Print • This Forum is closed for replies.    
Subject Difference between Lat Long WGS84 and GCS_WGS_1984 
Author Amy Ramsdell 
Date Jul 09, 2008 
Message What is the difference between Lat Long WGS84 GCS_WGS_1984 coordinate systems? They appear to be very similar to me, however you get that Geographic Coordinate Systems Warning message when you add one coordinate system on top of the other in ArcMap. What type of projection is involved when you use ArcToolbox's Project tool to convert one to the other?

Thanks,
Amy 
   
Report Inappropriate Content • Top • Print • This Forum is closed for replies.    
Subject Re: Difference between Lat Long WGS84 and GCS_WGS_1984 
Author Melita Kennedy 
Date Jul 09, 2008 
Message Hi Amy,

They're just "WGS84" as defined by different software packages. There's no difference in practice. Although you get the warning message in ArcMap, you can ignore it. Even setting a custom geographic transformation, won't change your data's coordinates.

The Project Tools (vector/raster) won't let you convert between them, because they are seen as different. You would have to use the Create Custom Geographic Transformation tool (9.2 and up) to define a transformation. Use geocentric translation method and leave the parameters set to zeroes.

Melita 
  Melita Kennedy
ESRI Product Specialist 
   
Report Inappropriate Content • Top • Print • This Forum is closed for replies.    
Subject Re: Difference between Lat Long WGS84 and GCS_WGS_1984 
Author Amy Ramsdell 
Date Jul 10, 2008 
Message Thanks Melita!! 
   
Report Inappropriate Content • Top • Print • This Forum is closed for replies.    
Subject Re: Difference between Lat Long WGS84 and GCS_WGS_1984 
Author Michael Ross 
Date Sep 29, 2009 
Message Thanks, Melita. 
  Michael R. Ross