Pipeline reduction

The eclipse command lwjitter can be used as a way to quickly reduce the data. The command uses an initialisation file, which contains parameters that define how the recipe runs. To generate one, type lwjitter -g lwjitter.ini at the prompt and this will create an initialisation file called lwjitter.ini. This file can be edited and modified by the user to setup some parameters.

The recipe reduces data by:

• classifying the input frames into those taken with the secondary at either side of the nod, i.e. positions A and B.
• computing (A-B)/2. Each frame shows one positive and two negative objects.
• computing the offsets between frames. Initial estimates are taken from the FITS headers and further refined through cross-correlation.
• registering the frames and stack into a single image.