Search
Text Size:
Smaller Text Normal Text Larger Text

Facebook page

Twitter profile

YouTube channel

ALFOSC Sequencer Command Documentation

Go to the SEQUENCER Reference Manual Main Page.

Instrument : ALFOSC
Observing Mode: ANY IMA SPEC POL
Command Type: ANY DATA DET DISP INST TEL
Usage: BASIC GENERAL STAFF
Description: SHORT LONG

SystemCommandArgumentsDescriptionType
alfosc allopen [-e] Will move all ALFOSC/FASU optical wheels to the OPEN position. Only wheels that according to the ALFOSC status are not already OPEN will be commanded to move. FASU wheels will always be commanded to move. INST
alfosc wheels [-e] [-s <slit>] [-g <grism>] [-c <crossdisp>] [-f <filterID>] [-d <diffuserID>][-nowait] [-forceFASU] Script to setup all 5 ALFOSC wheels, in quickest possible way. Possible arguments are:
  • -s <slit>   aperture-wheel item string
  • -g <grism>   grism string
  • -c <crossdisperser>   crossdisp grism string
  • -f <filterID>   filter ID number
  • -d <diffuserID>   diffuser ID number
  • -nowait   exit while wheels are moving
  • -forceFASU   force the FASU wheels to move even when at required position
Each wheel defaults to the OPEN position, unless it needs to be put to a different position as requested through the command-line arguments. Consequently, without any arguments alfosc.wheels puts all wheels to open. The script uses alfosc.optics to check the feasibility of the requested setup. If feasible, the wheels will be moved to put the requested items in the beam. If wheels are already in the correct position they will not be exercised, except for the FASU wheels when flag -forceFASU is given. If a requested setup is not possible, an error will result, and no wheels will be moved. Note: grism/slit strings should be unique. A list of optical items can be found here. Note: filter ID numbers can be found here. Note: the Focus_Pyr is considered a grism!! Note: for spectroscopy the horizontal/vertical requirements for the optical elements are tested.
Usage examples:
  • alfosc.wheels -f 74   sets up for imaging with filter #74
  • alfosc.wheels -g Focus_Pyr   sets up for focusing without filters
  • alfosc.wheels -s Slit_1.0 -g "#4"   sets up for spectroscopy with slit 1.0" and Gr#4
  • alfosc.wheels -s Slit_1.0 -g "#4" -f 93   sets up for spectroscopy with slit 1.0" and Gr#4 and blocking filter #93
  • alfosc.wheels -s Ech_0.8 -g "#9" -c "#10"   sets up for Echelle spectroscopy with slit 0.8" and Echelle Gr#9 and cross disperser Gr#10
INST

In scripts, the syntax alfosc.<command> should be used.
If a part of a command is written in <angle brackets>, this is an argument that should be replaced with a value.
If a part of a command is written in [square brackets], this is an optional argument or flag.
When available, the optional flag -d will write extended debugging information to the log.
When available, the optional flag -e will show the script on standard output instead of executing the commands.
When available, the optional flag -t will only make a simulated exposure. Useful for testing scripts.

Type definitions:
DATA: All commands related to handling/modifying data (editing fits-headers, post-processing etc.).
DET: Commands related to operations with the detector.
DISP: Commands related to displaying images on the instrument computer.
INST: Commands related to operations with the instrument.
TEL: Commands related to operations with the telescope.

Back to top Last modified: January 26 2023