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The Cassegrain A & G Box

The layout of the A&G unit is shown in Figure  5. It is described in some detail by P.A. Ellis in ING La Palma Technical Note no. 56. The unit provides acquisition, guiding and calibration facilities for all Cassegrain instruments. In the upper half of the A&G box a series of 45 degree mirrors direct light to the various ports around the circumference of the A&G box. Three of these are relevant for imaging.

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Figure 5: Cutaway view of the Cassegrain A&G box



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Wed Sep 17 12:36:20 BST 1997