Introduction

Integral field spectroscopy (IFS) is a technique to obtain both spatial (x,y) and spectral (λ) information of a more or less continuous area of the sky simultaneously on the detector. Only a few instrumental concepts allow 3D information on 2D detectors to be obtained, and all of these are based on field splitters such as fibre bundles, lens array, or image slicers (see Figure 7.1) to sample the field of view. Each sampled element is then dispersed using a classic spectrograph and produces a spectrum on the detector. Depending on the field splitter used, the geometry of the spectra on the detectors may be very different. This diversity leads to the creation of very specific reduction techniques and/or packages, i.e. one per instrument built (e.g. P3d, Becker, 2001). Combined with the inherent complexity of 3D techniques, such software diversity has reduced the use of IFS for decades to a handful of specialists, mainly those involved in the teams building such instruments.

Conscious that this would be a handicap IFS specialists Walsh and Roth (2002) have started to standardize techniques and tools for integral field units (IFU). Recently, the Euro3D Research Training Network (RTN), whose aim was to promote 3D spectroscopy all over Europe (Walsh and Roth, 2002), made a great effort to create a standard data format (Kissler-Patig et al., 2004) for storing and exchanging 3D data, developing an application programming interface, API (Pécontal-Rousset et al., 2004), to ease the use of such a data format and creating a visualization tool (Sánchez, 2004) usable by any existing IFU.