Guiding System

The general layout of the Guiding system is shown in Figure 5.

A remotely driven XY slide simultaneously moves two coherent optical fibre bundles over the focal plane (see also Figure 4). An area of 30$\text{'}2$ (2 $$x 15$\text{'}2$) is available for guiding purposes. Each bundle has a field of view of 18$$ x 18 arcsec $2$ on the focal plane.

 
Figure 5: Guiding system

The Guiding unit is equipped with a filter wheel housing up to six filters. The filters must be circular and 25mm in diameter. In the standard configuration the following filters are installed: CLEAR, BG38, GG495, OG530, and RG630.

The two guiding bundles are focussed onto a standard CCD autoguider head with thermoelectric cooler, through a prism and a lens (magnification 1:1).