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
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.
Any time you change filters, or otherwise move the filter wheel by hand,
you will have to reinitialize the spectrograph
from the Motor Control
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.
Support Astronomers (firstname.lastname@example.org)
Last modified: Tue Jul 17 18:35:31 PDT 2012