The invention relates to a method for acquiring the coordinates of a trigger point (P) of a projectile (4) above a field part (1) on which a target (5a, 5b, 5c) is located. The method is characterized in that it comprises the following steps: emission of at least one laser pulse having a pre-determined duration and directed towards the target (5a, 5b, 5c); reception of the images reflected with a receiver equipped with means for the synchronous visualization of the laser pulses originating from a piece of observation of the field part (1); recovery of the coordinates of a desired trigger point (P) when the operator has chosen a location after the piece of observation was moved. The invention also relates to a fire-control system using such a method.