This is a collection of tutorials for the reduction GNIRS keyhole imaging data with DRAGONS.

GNIRS is a spectrograph. It uses a keyhole to image a small area of the sky and acquire targets. The use of the GNIRS keyhole is not recommended for imaging but it has been used in that capacity in the past when there were no other options immediately available. The quality of the data, and therefore of the reduction is somewhat unpredictable. The quality of the reduction critically depends on the quality and the availability of the calibration frames, the flat fields in particular.

In here are tutorials that you, the reader, can run and experiment with. This document comes with a downloadable data package that contains all the data you need to run the examples presented. Instructions on where to get that package and how to set things up are given in Downloading the tutorial datasets.

Given the limited usefulness and general usage of this keyhole imaging mode, we provide here only one example, a point source dithered observation. We show how to reduce the sequence in two different ways:

  • From the terminal, using the command line. (Example 1-A)
  • From Python, using the DRAGONS classes and functions. (Example 1-B)