Calibration of the external parameters of multiple cameras is an essential step to accurately determine the relative position and orientation of cameras in multi-camera systems, especially in applications such as robot workspace tracking for safety, trajectory planning, or process control. Traditional methods using ArUco markers exhibit instability in position estimation, especially in situations where the axis of the markers intersects the camera axis. This inaccuracy can be partially eliminated by using a 3D calibration object (gridboard), with multiple visual markers. Our study focuses on the effect of different gridboard tilt settings on its detection accuracy. This paper presents the experimental measurement design, a new gridboard design, and a detailed evaluation of the measurement of the effect of different gridboard tilt settings on detection accuracy. Our findings provide an improvement in gridboard detection accuracy, leading to more accurate estimation of the relative position and orientation of multiple cameras at the sites.