Visualization of Deviations in Coordinate Transformations

Sammanfattning

Coordinate transformations are essential in geodetic workflows, but current tools such as GTRANS primarily visualize deviations in the horizontal plane (X and Y), often neglecting the vertical component (Z). This omission can lead to misinterpretation of elevation-related distortions, which are crucial in precision-dependent applications. This study investigates how vertical deviations can be effectively visualized alongside horizontal components using three geo-visualization strategies: color-coded 2D, symbolic 2D projection, and interactive 3D vectors. A convergent mixed methods approach was used, involving seven participants who completed two tasks: estimating vertical deviation and identifying spatial outliers. The results show that no single visualization method is optimal in all cases. However, separating the Z component from X and Y improves clarity. The symbolic 2D projection yielded the highest accuracy in technical tasks, while 3D visualization was most effective for spatial understanding and communication. The color-coded 2D method enabled fast scanning but had perceptual limitations. The study concludes that vertical deviation should be explicitly visualized in transformation tools, and that the choice of visualization should align with user goals, whether focused on accuracy, speed, or interpretability.