The cycle by which the place of an obscure where plane table is still up in the air and plotted o the arrangement with the assistance of at least two distinct station whose position are as of now plotted on the arrangement. In this technique, the view passes from obscure focuses to known places and the beam drawn is called as resector.

Let accept 2 pts An and B are plotted on a drawing sheet an and b.

Presently with assistance of an and b, we need to plot position of instrument 'c'.

Presently direction of plane table at 'c' the crossing point of two beams from an and b will give right area of instrument.