How to create Finding Charts for Service Mode

In general, a finding chart has to be attached to each OB. Exceptions are given in the instrument-specific rules. Please read the P2PP3 User Manual for a detailed description on attaching finding charts to OBs.

General Finding Chart Requirements

Regardless of the instrument, finding charts must have all the following characteristics:

  • Clearly indicate the Observing Run ID.
  • Clearly indicate the PI Name.
  • Clearly indicate the OB Name or Target Name, as used in the OB to which it is attached.
  • The target(s) position(s) must be clearly indicated.
  • The entire instrument field-of-view must be shown.
  • North and East must be clearly indicated.
  • The scale must be indicated by drawing a bar and writing the bar length in arcseconds or arcminutes.
  • The wavelength range of the image must be indicated. Whenever possible, finding charts should have similar central wavelength to observations (e.g. DSS charts are often inappropriate for IR observations near the galactic equator).
  • The images should be negative, i.e. dark objects on light background.
  • The output files must be in JPEG format and their size must be less than 1 Mbyte.
  • Positions of spectroscopic acquisition reference stars, if any, should be marked.
  • Spectroscopic finding charts must indicate the slit(s) position(s) clearly (unless slits are aligned along parallactic angle)

Please verify that finding charts have sufficient quality and resolution. This can be easily done from within P2PP by using the View Finding Chart option in the Finding Charts menu of the main P2PP interface (see also the P2PP User Manual).

Skycat Finding Chart tool

Although in most cases valid finding charts can be produced with any software tool able to produce output files in JPEG format, ESO recommends the use of the SkyCat-based finding chart tool. This tool provides a user-friendly interface to easily produce finding charts with the general characteristics described above.


Additional rules for KMOS finding charts

In addition to the general requirements for finding charts, the following requirements should be fulfilled:

  • The KARMA tool must be used for the generation of finding charts. The finding charts prepared with KARMA must comply with the general specifications (see above). The finding chart plugin distributed with the KARMA software provides a convenient way to do so.
  • KARMA-based finding charts must be saved in jpeg format from the KARMA File -> Make finding chart... window and must contain an overlay of the full KMOS field clearly showing the pick-off arm geometry. The high resolution images generated in this way will allow to verify at the telescope the successful acquisition of the reference objects and the science targets.
  • For observations where the acquisition is perforemd on reference stars, which are not science targets, two finding charts are required. One showing the pick-off arm configuration for the acquisition, the other showing the pick-off arm configuration for the science targets.
  • Finding charts for the mosaic mode should show the mosaic position on the target as well as the sky position.
  • If no background image was used in KARMA, still a finding chart is needed showing the arm configuration.
  • No finding chart is necessary for standard star observations.

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