A conveyor element (2) of a conveyor device conveys bar-shaped products (1) orthogonal to a longitudinal direction (x) of the bar-shaped products (1) oriented in a conveying direction (y). A trigger device (3) provides a trigger signal (S) each time the conveyor element (2) has travelled a predetermined interval. Based upon the respective trigger signal (S), an image (B) is acquired by a camera (4). The image (B) shows front ends of the products (1) in a respective section of the conveyor element (2) corresponding at least to the predetermined interval. Based upon the acquired images (B), the number of bar-shaped products (1) conveyed by the conveyor element (2) is determined.