Light bending curves from the exact Eq. (2) (solid lines), compared to those from the approximate Eq. (18) (dashed red lines) for R = 2r_s, R = 3r_s, and R = 5r_s. The dotted blue line represents the threshold from trajectories without a turning point (0 ≤ α ≤ π/ 2) to trajectories with a turning point (π/ 2 ≤ α ≤ α_max). The exact light bending curve for R = 1.55r_s is also plotted (dotted-dashed orange line) to show strong-field effects. The lower panels show the difference between the curves from the original and approximate equations.