It operates in the range 1.0–2.3 μm. The experience at the German Vacuum Tower Telescope (VTT), located at the same observatory, demonstrated that the most used spectral regions are those at 1.083μm (including the photospheric Si I and the chromospheric triplet He I) and at 1.565μm (with a number of iron lines including a line with g=3). As an example for the 1.565μm region: Five accumulations of 30ms exposure time each in the 4 polarimetric states yields a signal-to-noise ratio of 1000. In this case one scan step takes 3 sec.