This routine was originally developed from the CZ routine that configured the instrument to scan various sources, either by reading a configuration file (CZ.CFG within the data directory) or by entering in the configuration parameters as prompted.

The CA routine configures the instrument to scan various sources, either by reading a configuration file (CA.CFG within the data directory) or by entering in the configuration parameters as prompted and is used to scan a He-Cd Laser emitting at 325 nm or 3250 angstroms through a double convex lens that is directed into the UV dome. This single wavelength source is then scanned and measured over a range of wavelengths (usually 2900 - 3280 angstroms) to determine the stray light characteristics of the instrument.

The scanning has been modified to have a variable wavelength increment to collect the most important data at the highest resolution: 4 at less than 3100, then 2 up to 3200 and finally 1 to the maximum wavelength