Orac-dr is a data-reduction pipeline operating at UKIRT, JCMT, the AAT and forms the basis of the operational pipeline at LCOGT. The pipeline reduces and displays multi-frame observations soon after they are read from the detector. This allows observers to assess the quality and suitability of their data in near real time but Orac-dr is also used to produce the final archive-delivered products using the same code base.
SUN/230 presents an overview of Orac-dr, general facilities like its display system, and it explains the differences between a pipeline and a traditional reduction package. Put briefly, Orac-dr uses a few data headers to direct the data reduction. Amongst these headers is the name of a recipe. A recipe is a series of high-level instructions such as “make a mosaic” or “divide by a flat” that reduces an observation comprising one or more data frames. The implementation of each of these instructions is through a Perl script—called a primitive—which calls Starlink packages such as Ccdpack and Kappa, to actually do the processing of the bulk data.
This document describes how to use Orac-dr software on Starlink to reduce optical imaging data from the Las Cumbres Observatory Global Telescope Network (hereafter LCOGT; [1]) consists of data taken from one of the LCOGT instruments; LCOSBIG, LCOCC, LCOSINISTRO, LCOSPECTRAL or LCOFLI.
In an attempt to make this document clearer to read, different fonts are used for specific structures.
Observing modes are denoted by all upper case body text (e.g. FLATFIELD).
Starlink package names are shown in small caps (e.g. Smurf); individual task names are shown in sans-serif (e.g. makebias). Orac-dr recipes and primitives are also shown in sans-serif and are always upper case (e.g. REDUCE_BIAS).
Content listings are shown in fixed-width type (sometimes called ‘typewriter’). Extensions and
components within NDF (SUN/33) data files are shown in upper case fixed-width type
(e.g. HISTORY
).
Text relating to filenames (including suffices for data products), key presses or entries typed at the
command line are also denoted by fixed-width type (e.g. % kappa
), as are parameters for tasks which
are displayed in upper case (e.g. METHOD
).
References to Starlink documents, i.e., Starlink User Notes (SUN), Starlink General documents (SG) and Starlink Cookbooks (SC), are given in the text using the document type and the corresponding number (e.g. SUN/95). Non-Starlink documents are cited in the text and listed in the bibliography.
File name suffices represent the text between the final underscore character and the three-letter .sdf extension. For example, a file named lsc1m005-fl07-20140717-0173-d02_bp.sdf has the suffix _bp.