The Quick Look tool is designed to allow users to quickly assess the quality of their data. It automatically produces simple 1D extractions of science data with a reasonable guess for the target of interest (selectable as either the highest peak or the most central peak in the spatial direction); attempts a sky subtraction using two sidebands (which will also subtract the bias from the raw frame), and produces a 1D extraction.
For arcs, automatic wavelength calibration is attempted. The accuracy of this is appropriate for the spirit of a quick look tool and is typically ~2A. This allows the observer to check that the wavelength range of interest is being covered and to identify spectral features in science spectra. This is not intended to be a final science-quality level reduction and there are a number of caveats on the extraction and calibration process listed below. However, for some users, this may be entirely sufficient for their science needs. Even if it is not precise enough, it can be used as a starting point for a more careful reduction and notes on this are given belowhere https://topswiki.saao.ac.za/index.php/Using_QL_outputs.
<gallery>FullSci.png|Overview of GUI</gallery>
== Change Log ==
'''* 21 December 2016:''' Creation of this page. Initial notes on using the QL GUI, now that the software is stable. Additional details, including videos showing common tasks will be added in the near future. For questions about anything on this page, or use of the software, please email David Gilbank "gilbank AT saao dot ac dot za"
== Quick Start ==
'''Other notes:''' Again, the extraction is only carried out on the individual image (named in the filename). The data has been flipped in x such that the output, extracted spectra run blue to red in increasing x. If comparing with the raw data, keep this in mind.
MORE INFO ON HOW TO USE THESE AS A STARTING POINT FOR AN IRAF REDUCTION WILL BE PROVIDED IN THE NEAR FUTUREFor using these as the starting point for your '''science-quality reduction''': https://topswiki.saao.ac.za/index.php/Using_QL_outputs
=== .json file ===
=== Edges of 2D spectrum ===
'''Please don't modify software without discussing and clearing the modification with the software developers or instrument PI.''' To edit the '''bounds of the 2D spectrum''' (cyan lines in 2D plot window) edit as root the following file:
'''/usr/local/etc/qlgui/pars.json'''
The upper and lower bounds of the slit (which can be read off the 2D plot window using the cursor) are given by '''sl0''' and '''sl1''' respectively for the given grating name. e.g. for grating 5, the upper and lower bands are gr5_sl1 and gr5_sl0. Edit the numbers appropriately and resave the file. The changes should take effect the next time a spectrum is loaded.
In rare cases, the automatic wavelength calibration may fail. The "WLC advanced" tab provides settings to tweak the method used in the fitting. The 2x2 grid of plots on the left show some useful diagnostics of the fitting.
Suggestions for parameter adjustments are given next to the various options on the lower right of the screen. After adjusting any of these, please make sure to reload the current frame on the main tab (not the WLC advanced tab) for the changes to take effect. Note: if the GUI is restarted, these settings will revert to their default values. If you find a set of values which work better than the defaults for an unusual arc/grating angle (or need help adjusting settings), please email David Gilbank mailto:gilbank"carel AT @saao.dot ac.dot za " for these to be incorporated into the QL software. The default values should be robust for the most commonly used setups.