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Next: Below-the-Slit Viewing Previous: Telescope Secondary Focus Up: Telescope Focus and Aperture Viewing Optics

Above-the-Slit Viewing

Viewing the aperture plate from above yields about a 2.5.5 arcmin field (mm). Normally, the acquisition TV camera [B] views the aperture plate from above. To see the same picture visually, a relay mirror directly above the TV must be rotated by turning the selector knob [P] so that the handle indicator aligns to horizontal. Uncap the viewing eyepiece by pulling off the captive cover [J] and focus by twisting the threaded eyepiece holder.

Pat Hall - Wed Oct 4 11:02:37 MST 1995