Describe back sighting method of orientation of plane table surveying.
1 Answer
Backsight method of orientation
1. Assume we have to orient the table at next station ‘B’ represented on paper by point ‘b’.
2.the line ‘ba’ is drawn on previous station ‘A’.
3.the alidade is kept on line ‘ba’ and the table is turned around its vertical axis such a way that line of sight passes through ground station ‘A’.
4. When the plotted line ‘ab’ coincides with line ‘AB’ and table will be oriented.
2.the line ‘ba’ is drawn on previous station ‘A’.
3.the alidade is kept on line ‘ba’ and the table is turned around its vertical axis such a way that line of sight passes through ground station ‘A’.
4. When the plotted line ‘ab’ coincides with line ‘AB’ and table will be oriented.