;batch file called from calculate_ring_brightness_plus_planet

;x-east in the imageplane,y-north,z-toward the spacecraft

;norm_ring_plane=[0.,1.,-1.*tan(double(ring_facing_angle_deg)/180.*!pi)+1e-12]
norm_ring_plane=[0.,-1./tan(ring_facing_angle_deg/180.*!pi)+1e-12,1.]
norm_ring_plane_abs=norm(norm_ring_plane);(norm_ring_plane##transpose(norm_ring_plane))^0.5
norm_ring_plane=norm_ring_plane/norm_ring_plane_abs(0)
;print,'norm_ring_plane',norm_ring_plane