Fig. 1. A simulated star map without noise

Fig. 2. A star map superimposed with sun straylight noise

Fig. 3. Effect drawing of a star image spot with white noise, background threshold and straylight slope noise

Fig. 3. [in Chinese]

Fig. 4. Effect of model slope estimate error Δk₁ on centroiding error component of x-coordinate

Fig. 5. Effect of model slope estimate error Δk₂ on centroiding error component of x-coordinate

Fig. 6. Effect of model slope estimate error Δb on centroiding error component of x-coordinate

Fig. 7. A sun straylight gray image generated from a nonlinear model

Fig. 8. Eight window locations on the diagonal with an interval of 128 pixels

Fig. 9. Straylight images produced by a sun simulator in lab

Fig. 10. Three-dimensional display of the 4th gray image (α_SCA=56°) in Fig. 9

Fig. 11. Gray distribution of diagonal pixels of sun straylight image and the eight window locations

Fig. 12. Standard deviation comparison between three centroiding methods at eight windows

Fig. 13. Absolute error curves of centroided x-coordinate by three methods