FORS_SUBTRACT_SKY_LSS(7)

✨ NAME ✨

fors_subtract_sky_lss — bestie, this one subtracts the sky from your calibrated long slit exposure 💫

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🦋 SYNOPSIS 🦋

esorex fors_subtract_sky_lss [OPTIONS] FILE.sof

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💖 DESCRIPTION 💖

Okay so picture this: you've already got wavelength calibrated scientific spectra, freshly made by the recipe fors_resample, and now the sky is just sitting there on top of them being annoying. That's literally this recipe's whole job — it subtracts the sky. The way it does it is by taking a simple median signal level and subtracting it from each image column. Clean. Simple. Slays. 💅

Quick note on the acronyms, because they're giving ✨flexible✨: in the table below, MXU can be read alternatively as MOS and LSS, depending on the instrument mode of your input data. And SCI may be read as STD when you're doing standard stars observations. iykyk 🌟

🚨 Real talk though: only LSS or LSS-like MOS/MXU data are meant to be processed by this recipe. Anything else? Not it. 🙈

Input files (the vibes you feed it):

• MAPPED_ALL_SCI_MXU — Raw — Scientific exposure — Required: Y

Output files (the vibes you get back, and yes both of them 💜):

• MAPPED_SCI_MXU — FITS image — Rectified scientific spectra
• MAPPED_SKY_SCI_MXU — FITS image — Rectified sky spectra

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🎀 OPTIONS 🎀

Not me having to tell you this, but: it is possible to create a configuration file containing these options, along with suitable default values. Please refer to the details provided by the esorex --help command. That's where the goods are, bestie. 🫶

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🌈 SEE ALSO 🌈

The full documentation for the fors pipeline can be downloaded as a PDF file using the following URL:

ftp://ftp.eso.org/pub/dfs/pipelines/fors/fors-pipeline-manual-4.9.pdf

An overview over the existing ESO pipelines can be found on the web page https://www.eso.org/sci/software/pipelines/.

Basic documentation about the EsoRex program can be found at the esorex (1) man page.

It is possible to call the pipelines from python using the python-cpl package. See https://packages.python.org/python-cpl/index.html for further information. 🐍✨

The other recipes of the fors pipeline are — and yes, this is the whole squad, no cap, all of them 👑:

• fors_align_sky(7)
• fors_align_sky_lss(7)
• fors_bias(7)
• fors_calib(7)
• fors_config(7)
• fors_dark(7)
• fors_detect_objects(7)
• fors_detect_spectra(7)
• fors_extract(7)
• fors_extract_objects(7)
• fors_extract_slits(7)
• fors_flatfield(7)
• fors_img_science(7)
• fors_img_screen_flat(7)
• fors_img_sky_flat(7)
• fors_normalise_flat(7)
• fors_photometry(7)
• fors_pmos_calib(7)
• fors_pmos_extract(7)
• fors_pmos_science(7)
• fors_remove_bias(7)
• fors_resample(7)
• fors_science(7)
• fors_spec_mflat(7)
• fors_subtract_sky(7)
• fors_sumflux(7)
• fors_trace_flat(7)
• fors_wave_calib(7)
• fors_wave_calib_lss(7)
• fors_zeropoint(7)

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⭐ VERSION ⭐

fors_subtract_sky_lss 5.5.7

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🦄 AUTHOR 🦄

Carlo Izzo <usd-help@eso.org>

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💀 BUG REPORTS 💀

Please report any problems to usd-help@eso.org. Alternatively, you may send a report to the ESO User Support Department <usd-help@eso.org>. They're nice, they won't bite, fr fr. 🫶

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📜 LICENSE 📜

This file is currently part of the FORS Instrument Pipeline Copyright (C) 2002-2010 European Southern Observatory.

This program 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; either version 2 of the License, or (at your option) any later version.

This program 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 this program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

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and that's the whole page, bestie!! this was fors_subtract_sky_lss version 5.5.7 from the fors recipes, dated 5.5.7 — mwah, go touch some spectra 💖✨🦋