Orthometric Height Conversion

Orthometric height conversion is performed by calculating the datum shift based from modeled values.
The resulting datum shift is displayed.
The converted orthometric height is displayed only if the height to be converted from was not left blank.
***** See input format details below *****

ENTER North Latitude :........

ENTER West Longitude :......

ENTER Orthometric Height : -- Entry is Optional; Default units (meters) --

SELECT Vertical Datum :... NGVD 29 NAVD 88 -- of the entered height --

If the orthometric height is unknown DO NOT ENTER ZERO; leave the entry field BLANK !


Latitude and Longitude are REQUIRED:

Position may be entered in any of the following three formats:
  1. degrees, minutes and decimal seconds ( xxx  xx  xx.xxx)
  2. degrees and decimal minutes          ( xxx  xx.xxx)
  3. decimal degrees                      ( xxx.xxxxx)

Note: There MUST be one or more blanks between entry fields
      Decimals can be keyed commensurate with the field's precision, but are not required.

Orthometric Height to be converted FROM is OPTIONAL:

Height may be entered in either meters or U.S. survey feet:
  1. meters:  xxxx.xxx
  2. feet  :  xxxx.xx  FT  ( MUST include FT or ft for feet !)


It is possible that the datum shift computation may not succeed.
There could be many reasons for this, including position and height entry errors. In such a case, an error code is returned.
Questions concerning the datum shift computation process may be mailed to NGS