Download FIES Automatic Data Reduction Software version 1.0 User Manual

4.2
Data reduction tasks (steps)
21
• Preprocess frame
• Subtract BIAS
• Subtract scattering
• Divide by 2-D flat
• Plot cross-order profile
• Determine spectrum shift
• Extract spectrum
• Correct for blazeshape
• Add wavelengths
• Adjust wavelengths
• Autoplot reduced spectra
4.1.4
CalibCalc
The CalibCalc reduction mode is a special mode that is optimized for calculating
reference data, such as combining biases and flat fields, order finding and tracing
and wavelength calibration. This mode is automatically enabled when the user
starts tasks from the ’Calibration frame’ (see section 3.3). Differing from the other
reduction modes, these tasks are not automatically executed together. Instead, the
user will have to execute these one at a time. The tasks included in this mode are :
• Create combined BIAS
• Create combined FLAT
• Find order locations
• Find interlaced order locations
• Plot order locations
• Create normalized combined FLAT
• Find wavelength solution
• Find interlaced wavelength solution
4.2
Data reduction tasks (steps)
Below follows a short description of each of the data-reduction tasks. More detailed
information on the calculations can be found in the comments of the source code.
The tasks make use of two external packages for calculations. Numerical array operations on frames or subsets of frames are performed with the NumArray package,
while specific echelle reduction tasks (for example, optimal order extraction) are
performed with IRAF. In the case a tasks calls IRAF to do the work, IRAF parameter configuration files are used to determine the behaviour of the IRAF tasks (see
the appendix about the location of these files). Plotting is done either by the Biggles plotting package (for non-interactive plotting), or the IRAF task echelle.splot
(interactive).