sza_file fileThis option is useful if you want to simulate an instrument which scans so slowly that the solar zenith angle may change significantly during the wavelength scan. The file must have two or three columns. Column 1 is the wavelength, in nm, and column 2 the corresponding solar zenith angle. Optionally the third column may contain the corresponding solar azimuth angle. The solar azimuth angle is only needed when calculating radiances. The wavelength grid may be freely set. The solar zenith and azimuth angle will be interpolated to the wavelength grid used for the radiation calculation. Comments start with #. Empty lines are ignored.