Intensity of scattered radiation for a uniform source of unit brightness using the Paranal extinction curve (see Sect. 2.1). Contributions of scattered light into the line of sight are shown for Rayleigh (solid lines) and Mie scattering (dashed lines) and zenith distances from 0° to 80° in 10° steps plus an extreme value of 85°. Except for Rayleigh scattering at very short wavelengths, the scattering intensities increase with zenith distance.