Hand-held observation device comprising - a laser rangefinder unit configured to measure a distance along a measurement axis between the observation device and a target point on a remote target and to generate range-measurement data; - a camera configured to capture images of the target and to generate image data; - a pose detection unit configured to detect a pose of the observation device and to generate pose data; - a display unit configured to display an image of the target based on the image data together with the range-measurement data to a user of the observation device; - a user input device configured to receive user inputs from the user; and - a digital processing unit comprising a memory, wherein the digital processing unit is configured - to receive a measurement request from the user via the user input device, - to receive image data from the camera, - to continuously receive the pose data from the pose detection unit, - to trigger range measurements to one or more target points using the laser rangefinder unit, - to receive range-measurement data from the laser rangefinder unit, - to calculate, based on the pose data and on the range measurement data, 3D target point coordinates for the one or more target points, and - to store the 3D target point coordinates in the memory, characterized in that the digital processing unit is further configured - to compare the stored 3D target point coordinates with the measurement request to determine one or more regions with missing 3D target points coordinates, - to continuously monitor the pose of the observation device based on the continuously received pose data, - to detect, based on the continuously monitored pose, when the measurement axis of the laser rangefinder unit aims at one of the determined regions with missing 3D target point coordinates, and - to automatically trigger an additional range measurement of the laser rangefinder unit for measuring 3D target point coordinates in the region the measurement axis aims at. - a laser rangefinder unit configured to measure a distance along a measurement axis between the observation device and a target point on a remote target and to generate range-measurement data; - a camera configured to capture images of the target and to generate image data; - a pose detection unit configured to detect a pose of the observation device and to generate pose data; - a display unit configured to display an image of the target based on the image data together with the range-measurement data to a user of the observation device; - a user input device configured to receive user inputs from the user; and - a digital processing unit comprising a memory, - to receive a measurement request from the user via the user input device, - to receive image data from the camera, - to continuously receive the pose data from the pose detection unit, - to trigger range measurements to one or more target points using the laser rangefinder unit, - to receive range-measurement data from the laser rangefinder unit, - to calculate, based on the pose data and on the range measurement data, 3D target point coordinates for the one or more target points, and - to store the 3D target point coordinates in the memory, - to compare the stored 3D target point coordinates with the measurement request to determine one or more regions with missing 3D target points coordinates, - to continuously monitor the pose of the observation device based on the continuously received pose data, - to detect, based on the continuously monitored pose, when the measurement axis of the laser rangefinder unit aims at one of the determined regions with missing 3D target point coordinates, and - to automatically trigger an additional range measurement of the laser rangefinder unit for measuring 3D target point coordinates in the region the measurement axis aims at.