Purpose

This checklist describes the "emergency" LRIS-style procedure for aligning multiobject slitmasks on DEIMOS when the image header is faulty and does not contain the typical information on the positions of the alignment boxes.


Setup

The following steps would ideally be done in the afternoon in order to save time on sky; however, they can also be done during the night.
  1. Acquire direct slitmask image. This can be done in the afternoon via the DEIMOS Slitmask Imaging Widget, or can be an alignment image acquired on-sky as part of the fine alignment procedure.
  2. Create box coordinates file.

Alignment Procedure

This is essentially identical to the standard slitmask alignment procedure, with the exception of the step indicated in red below.
  1. Focus telescope and complete fine alignment.
  2. Complete fine alignment.
    In this step, you will refine the positions of the stars within their respective alignment boxes to achieve optimal centering of the slitmask.
  3. Set up for spectroscopy.
  4. Wait for FCS to settle. Do not start your exposure until the FCS GUI shows the FCS status as locked, or it may be smeared.
  5. Expose!

See Also