The FP-SPLIT slits consist of two sets of five slits; in each set the slits are all the same size. They are for use with the MAMA echelle gratings. It is possible to achieve high S/N data for bright targets, independently of the quality of the flat-field, by means of a special observing strategy wherein multiple spectrograms are obtained through these slits.
See Chapter 12 for more details on obtaining high S/N spectral data. Observations with this slit require a prior
PEAKUP.