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fcmaker finding chart example

Figure 1: a typical MUSE-WFM-AO finding chart generated by fcmaker.


I started developing fcmaker during my ESO Fellowship in late 2017. The code is being shared with the community, in the hope that it can be useful to others. But please note that fcmaker is not an official tool from the European Southern Observatory (and never will be).

As of P103, ESO implemented a Finding Chart Generation service directly into p2, called p2fc. p2fc is based on a direct fork of fcmaker (v103), but has since gone its own way.

As of P104, a p2fc binding has been added to the p2api via the generateFindingChart() function (which includes the option to use custom FITS files). This implies that fcmaker has no more raison d’être. I have therefore decided to stop actively maintaining fcmaker.

Instruments and modes implemented

  • MUSE: all modes

  • HAWKI: NOAO, TT-free AO, including fast photometry

  • XSHOOTER: all modes

  • ESPRESSO: all modes

  • targets with proper motions, ephemeris files

  • tutorial OBs on p2demo


As of P104, the development of fcmaker has officially stopped! I may still be pushing updates (see the Changelog for details) to meet some of my personal observational needs, but will make no efforts to maintain all of the code functionalities. You have been warned.


fcmaker is a Python3 module that offers a rapid, easy and automated way to generate ESO-compliant finding charts for observing blocks (OBs) located on p2. fcmaker relies on p2api to easily interact with the p2 database.

The design of the fcmaker finding charts is driven by their use at the VLT to support night time operations. They aim at providing a clear and accurate view of the expected execution of an OB, given its parameters (i.e. without any further manual input). Note that unlike p2, fcmaker does not perform any validation checks on the OB: it merely prints what they do, be it valid or not. In essence, fcmaker provides the user with the ability to visually check the content of an OB.

I expect/hope that fcmaker, despite being fully automated, will do a reasonable job for most OBs of the supported instruments and modes. Should you stumble upon a case where fcmaker utterly fails to do something useful/elegant, I’d be keen to know about it.


The operational spirit of fcmaker implies that, at times, its finding charts may not be the most ideal to design and prepare an OB.

For example, fcmaker voluntarily does not display the SGS area for MUSE WFM observations. Whereas it may be important at the design phase to ensure that a given SGS star can be accessible in all the OB steps, it is irrelevant for the execution of the OB itself, and would unnecessarily crowd the fcmaker finding charts.


Never blindly rely on what fcmaker does. If the finding chart generated by fcmaker looks different from what you expected, this means that:

  1. there is a real design flaw in your OB, or

  2. there is a yet undiscovered bug in fcmaker.

In those discordant cases, feedback will be greatly appreciated.

Copyright notice:

This file is part of the fcmaker Python module. The fcmaker Python module is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 3 of the License.

The fcmaker Python module is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with the fcmaker Python module. If not, see http://www.gnu.org/licenses/ .