Dear TBC users,
The GEOID18 grid files in the little endian and ASCII grid formats that were posted by NGS prior to November 26, 2019, contained errors in a small percentage of the grid cells (1 in 500). NGS has corrected the errors and replaced these files. Therefore, the TBC team has since incorporated these critical changes in the Coordinate System Database 88 (CSD88). Please see our ‘Check for Updates’ in TBC to install the latest changes.
ngs geoid csd88