Tilt Correction

Use the Tilt Correction menu option (LVTILT GX) to create a tilt level correction channel from an error difference channel. The correction is calculated as the first order trend through the level errors (differences) at each crossing.

Create a Tilt Level Correction Channel dialog options

Level error channel	The channel that contains the error data at the line crossings. This channel is normally created by loading the corrections from a correction table using the XLEVEL GX. Script Parameter: LVSHIFT.ERROR
Output correction channel	The name of a new channel that will be created to hold the calculated correction. Script Parameter: LVSHIFT.OUT
Maximum error	The maximum allowable error to be considered. The errors will be clipped to (+/-) this value before a trend is calculated Script Parameter: LVSHIFT.MAX
Process line types	"Selected" to process selected lines. "Tie" to process tie lines. "Lines" to process normal lines. Script Parameter: LVSHIFT.TYPE

Application Notes

Use the GX to calculate a trend (tilt) that can be removed from lines minimise levelling errors. The resulting correction channel can be subtracted from the unlevelled data using the LVCORR GX.