User's Guide to the Nickel Spectrograph

Table of Contents

Hardware Overview
Aperture Wheel
Filter Wheel
CCD Stage
Detector Characteristics
Software Overview
CCD User Interface
Motor Controller
Observing Hints
Calibration Lamp Spectra

Data Archive
Mt. Hamilton Homepage

Filter Wheel

The filter wheel has five positions, one of which (position 0) is always empty. The remaining four positions can hold 2" filters. A selection of broadband, order blocking, and neutral density filters are stored at the Nickel 1-m (in the wooden cabinet in the control room). In addition, any of the 2" filters in the 3-m filter library can be mounted in the filter wheel. Please fill out a checkout slip when removing filters from the library and return the filters when your observing run is completed.

Observers are responsible for checking and/or changing the contents of the filter wheel. The filter wheel is accessed from a panel on the west side of the telescope. Carefully move the filter wheel by hand to change filters or identify the contents of the wheel. Please use the filter handling tool when inserting or removing filters to minimize the chances of getting fingerprints on the filters. Always insert filters with the retaining clip facing up and the tapped hole to the outside of the wheel, as illustrated.

PositionReturn Code
Any time you change filters, or otherwise move the filter wheel by hand, you will have to reinitialize the spectrograph from the Motor Control software because the zero point for the filter wheel is lost when the wheels are turned by hand.

The name of each filter in each slot can be input into the Motor Control software. The software also returns the following codes for each filter position. Always double check the contents of the filter wheel before observing -- do not assume that the last observer has left the filter wheel as reported in the GUI.

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Last modified: Tue Jul 17 18:35:31 PDT 2012