HAWKI_TWILIGHT_FLAT_COMBINE(7)

👑 HAWKI_TWILIGHT_FLAT_COMBINE ✨

okay so bestie, welcome to hawki_twilight_flat_combine(7) — it's one of the lil recipe pages from the hawki recipes collection, and honestly? she's giving "quietly essential". let's get into it 💅

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🌸 NAME 🌸

hawki_twilight_flat_combine — the HAWKI twilight combination recipe. that's her. that's the whole name. iconic.

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🎀 SYNOPSIS 🎀

esorex hawki_twilight_flat_combine [OPTIONS] FILE.sof

yes babes, that's it. an EsoRex call, some options if u feel like it, and a .sof file. simple. clean. no notes. ✨

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🦋 DESCRIPTION 🦋

so like — hawki_twilight_flat_combine is the HAWKI twilight flat combine recipe, no cap.

what she does: takes a whole list of twilight flat frames and combines them into a mean frame. and then, if u want, she can also compare that output frame against a master twilight flat frame. cute, right? 🫶

now here's the part where u actually pay attention, because the program is picky about which files u feed it in the SOF. she accepts these:

• FLAT_TWILIGHT — a list of raw twilight flat images
• MASTER_DARK — a master dark frame
• REFERENCE_TWILIGHT_FLAT — optional reference twilight flat frame
• MASTER_BPM — optional master bad pixel map
• MASTER_CONF — optional master confidence map

lowkey important: if u don't hand over a reference twilight flat, then no comparison happens. zero. none. which means there will be no output ratio image — so don't come looking for one, bestie 😭

and if u do specify either a master bad pixel mask or a master confidence map, that gets used to help mask out bad pixels. slay. 🔥

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✨ OPTIONS ✨

here's the full menu, no skipping, every single one. 💖

• --lthr <float> — the low rejection threshold, for images that are underexposed. it's a float, default: 4000.0. the full name of this option for the EsoRex configuration file is hawki.hawki_twilight_flat_combine.lthr [default = 4000.0].
• --hthr <float> — the high rejection threshold, for images that are overexposed. float, default: 30000.0. full EsoRex config name: hawki.hawki_twilight_flat_combine.hthr [default = 30000.0].
• --combtype <str> — the combination algorithm. str, default: median. full EsoRex config name: hawki.hawki_twilight_flat_combine.combtype [default = median].
• --scaletype <str> — the scaling algorithm. str, default: multiplicative. full EsoRex config name: hawki.hawki_twilight_flat_combine.scaletype [default = multiplicative].
• --xrej <bool> — True if u want the extra rejection cycle. bool, default: True. full EsoRex config name: hawki.hawki_twilight_flat_combine.xrej [default = True].
• --thresh <float> — the rejection threshold, in sigma above background. float, default: 5.0. full EsoRex config name: hawki.hawki_twilight_flat_combine.thresh [default = 5.0].
• --ncells <int> — number of cells for data channel stats. int, default: 8. full EsoRex config name: hawki.hawki_twilight_flat_combine.ncells [default = 8].
• --prettynames <bool> — use pretty output file names? bool, default: False. full EsoRex config name: hawki.hawki_twilight_flat_combine.prettynames [default = False].

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also, fyi: u can make a configuration file holding all these options plus suitable default values. the details are in the esorex --help command. go look, she explains it better than i can 💜

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🌈 SEE ALSO 🌈

the full documentation for the hawki pipeline can be downloaded as a PDF file, right here:

ftp://ftp.eso.org/pub/dfs/pipelines/hawki/hawki-pipeline-manual-2.4.11.pdf

an overview over the existing ESO pipelines lives on this web page:

https://www.eso.org/sci/software/pipelines/

basic documentation about the EsoRex program is at the esorex(1) man page.

and yes, u can call the pipelines from python using the python-cpl package — more info at:

https://packages.python.org/python-cpl/index.html

the other recipes of the hawki pipeline, aka the whole friend group, are: hawki_cal_dark(7), hawki_cal_distortion(7), hawki_cal_flat(7), hawki_cal_zpoint(7), hawki_dark_combine(7), hawki_detector_noise(7), hawki_linearity_analyse(7), hawki_sci_jitter(7), hawki_science_postprocess(7), hawki_science_process(7), hawki_standard_process(7), hawki_step_apply_dist(7), hawki_step_basic_calib(7), hawki_step_combine(7), hawki_step_compute_bkg(7), hawki_step_detect_obj(7), hawki_step_photom_2mass(7), hawki_step_refine_offsets(7), hawki_step_stats(7), hawki_step_stitch(7), hawki_step_subtract_bkg(7), hawki_tec_filtchk(7), hawki_util_gendist(7), hawki_util_stdstars(7).

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💖 VERSION 💖

hawki_twilight_flat_combine 2.4.11. periodt. 💅

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👑 AUTHOR 👑

Jim Lewis <jrl@ast.cam.ac.uk> — we stan.

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💀 BUG REPORTS 💀

if something's broken, please report any problems to jrl@ast.cam.ac.uk. alternatively, u can send a report to the ESO User Support Department <usd-help@eso.org>. they're nice, don't be shy 🫶

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🌸 LICENSE 🌸

this file is part of the HAWKI Instrument Pipeline Copyright (C) 2015 European Southern Observatory.

this program is free software; u 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.

u should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.

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and that's the whole thing, bestie 🎀 this was hawki_twilight_flat_combine, version 2.4.11, from the hawki recipes manual — HAWKI_TWILIGHT_FLAT_COMBINE(7), in case u forgot where u were. go combine those flats. mwah 💋✨