Do either LASERTC, INNERTC, or RASTERTC provide standard gravity reductions?
No, these programs only calculate terrain corrections, they do not provide standard gravity reductions. However, a public-domain software package called OUTERTC is distributed along with the LASERTC, INNERTC, and RASTERTC. This package, originally written by Donald Plouff of the U. S. Geological Survey, not only provides standard gravity reductions, but can also correct for the effect of distant terrain. Being public-domain software, it is provided without charge.
