Choose a frame to upload your data:
- Why two frames? What's the difference?
- NGS has revised the CORS coordinates and absolute antenna calibrations. For a limited time, OPUS will provide access to both the current and previous frames. See FAQ & difference maps.
- NGS has revised the CORS coordinates and absolute antenna calibrations. For a limited time, OPUS will provide access to both the current and previous frames. See FAQ & difference maps.
- Which frame is best for me?
- Most users should choose the current frames, using the previous only for NAVD 88 orthometric heights, or positions consistent with existing NGS datasheets.
* note these will be superseded soon, when NGS completes the adjustment of the passive control network and release of GEOID12.
- Most users should choose the current frames, using the previous only for NAVD 88 orthometric heights, or positions consistent with existing NGS datasheets.
- Why is there no NAVD 88 orthometric height for the current frame?
- This is a temporary situation that will be resolved soon with the release of GEOID12 (see question above.) The current GEOID09 model was built from CORS96-derived ellipsoid heights, and therefore works best with the previous frame.
- This is a temporary situation that will be resolved soon with the release of GEOID12 (see question above.) The current GEOID09 model was built from CORS96-derived ellipsoid heights, and therefore works best with the previous frame.
- Will published solutions use the current or previous frames?
- Either, for now, but soon all published solutions will be updated to the current frames, with previous coordinates retained as superseded.
