Reduction paradigms

There are two paradigms for IFS data reduction. First, the `traditional' method, adapted from multi-object spectroscopy (MOS), where the output from each fibre is extracted by tracing the spectrum and accounting for wavelength-dependent distortion (normally referred to as the MOS paradigm). More recently, with the arrival of TEIFU where the fibre outputs are under-sampled by the detector, an alternative paradigm has arisen (usually referred to as the longslit paradigm). Although the independence of the spatial samples is lost due to the under-sampling of the point-spread function (PSF) by the detector, it can be shown that this is irrelevant so long as the target is critically sampled by the IFU; see Allington-Smith & Content (1998). Here the methods adapted from MOS cannot be used and the resulting dataset bears more resemblance to traditional longslit spectroscopy than to MOS data.