A method for making field measurements during surveying using a station or first surveying pole placed at a first location, and a second surveying pole placed at a second location, the station or first surveying pole comprising a first camera; a second camera at a first known distance from the first camera; and a first target; and the second surveying pole comprising a third camera; a fourth camera at a second known distance from the third camera; and a second target; the method comprising: acquiring a first image with the first camera while the second surveying pole is at the second location, the first image including the second target; acquiring a second image with the second camera while the second surveying pole is at the second location, the second image including the second target; the method being characterised by: acquiring a third image with the third camera while the second surveying pole is at the second location, the third image including the first target; acquiring a fourth image with the fourth camera while the second surveying pole is at the second location, the fourth image including the first target; and determining a spatial relationship between the first location and the second location based on: a position of the second target in the first image; a position of the second target in the second image; a position of the first target in the third image; a position of the first target in the fourth image; the first known distance; and the second known distance. the station or first surveying pole comprising a first camera; a second camera at a first known distance from the first camera; and a first target; and the second surveying pole comprising a third camera; a fourth camera at a second known distance from the third camera; and a second target; the method comprising: acquiring a first image with the first camera while the second surveying pole is at the second location, the first image including the second target; acquiring a second image with the second camera while the second surveying pole is at the second location, the second image including the second target; the method being characterised by: acquiring a third image with the third camera while the second surveying pole is at the second location, the third image including the first target; acquiring a fourth image with the fourth camera while the second surveying pole is at the second location, the fourth image including the first target; and determining a spatial relationship between the first location and the second location based on: a position of the second target in the first image; a position of the second target in the second image; a position of the first target in the third image; a position of the first target in the fourth image; the first known distance; and the second known distance. acquiring a first image with the first camera while the second surveying pole is at the second location, the first image including the second target; acquiring a second image with the second camera while the second surveying pole is at the second location, the second image including the second target; the method being characterised by: acquiring a third image with the third camera while the second surveying pole is at the second location, the third image including the first target; acquiring a fourth image with the fourth camera while the second surveying pole is at the second location, the fourth image including the first target; and determining a spatial relationship between the first location and the second location based on: a position of the second target in the first image; a position of the second target in the second image; a position of the first target in the third image; a position of the first target in the fourth image; the first known distance; and the second known distance. a position of the second target in the first image; a position of the second target in the second image; a position of the first target in the third image; a position of the first target in the fourth image; the first known distance; and the second known distance.