Question

Are .GDC files for vertical transformations reversible?

  • 28 November 2018
  • 1 reply
  • 1 view
M

I have converted data from NAD83 (CSRS) 1997 to NAD83 (CSRS) 2010, along with this conversion, vertical handling is converting the z values to CGVD2013.

I am now trying to reverse the transformation. I am able to successfully reverse the horizontal values using the (Reversed) transformation option. I am wondering if there is a reversed option for vertical .gdc files? or is a new file altogether required?

I am having no luck finding information online for this.

1 reply

daveatsafe
Rank
Userlevel 2
Badge +17

Hi @michoo,

The Vertical Handling option 'Orthometric height -> Geocentric or ellipsoidal height' is the reverse of 'Geocentric or ellipsoidal height -> Orthometric height'. You should choose the same grid file for each.

Reply


Community Stats

28,694
Posts
109,434
Replies
36,545
Members
Terms & ConditionsCookie settings
A product of
Safe Software respectfully acknowledges that we live, learn and work on the traditional and unceded territories of the Kwantlen, Katzie, and Semiahmoo First Nations.