DRAGONS Feedback

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This topic contains 4 replies, has 2 voices, and was last updated by  mschwamb 1 month, 4 weeks ago.

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  • #3262

    klabrie
    Keymaster

    We invite users of DRAGONS to share their comments and suggestions aiming to improve of the documentation and the user experience. While we aim to increase and improve the documentation over time, thanks to your contributions, we will be able to focus first on the immediate needs, on the aspects that are important to you.

    (Note, if you have data reduction issues with DRAGONS, please use the Helpdesk, category Gemini IRAF (since DRAGONS is not on the list yet).)

    #3271

    mschwamb
    Participant

    Hi,

    Congratulations on the release of DRAGONS. I was able tor reduce my Fast Turnaround data quickly. I reaqly like the command line ability and the python ability to interact with DRAGONS and installing it in its own conda enivronemnt

    I followed on the online tutorial. Since I have a small number of images I was using DRAGONS via the command line. The online examples and what I can find the read-the-docs about the reduce command is that if you have a list of science frames in a file and reduce @list reduce will at the last stage stack the images. I wanted to measure photometry individually. It would be nice if there was a way to have the images reduced one by one but not stacked. I could’t find out how to do that so I ran reduce on each science frame inidivudally on the command line.

    Also I wanted to make list of bias frames by date to process and also only reduce a portion of the science frames. The examples for epxressions that can be used with dataselect. I couldn’t see a way of selecting based on observation date.

    Thanks,

    ~Meg

    #3275

    klabrie
    Keymaster

    Thanks Meg. Great real use cases. This is very helpful to us. It is going to help us update the documentation.

    First the dataselect. The command is:
    dataselect --expr="ut_date=='2017-07-02'" *.fits -o 20170702.lis

    Problem is… there is a bug in dataselect that makes that fail. It’s fixed now. We are looking at a patch release around January-February 2020.

    Second, not doing the stacking. The users can modify any of the recipes even build their own. (There’s documentation on that, but only the most keen user will put the pieces together. We’ll improve that.) Here’s how you could do it.

    Check what the recipe looks like:
    showrecipes N20170614S0201.fits

    Then copy the pre-stack part of that recipe in your local directory, eg. in a file named “myrecipelibrary.py” (or whatever name you like):

    
       def reduce_nostack(p):
           p.prepare()
           p.addDQ()
           p.addVAR(read_noise=True)
           p.overscanCorrect()
           p.biasCorrect()
           p.ADUToElectrons()
           p.addVAR(poisson_noise=True)
           p.flatCorrect()
           p.fringeCorrect()
           p.mosaicDetectors()
    

    Then call your personal recipe with:
    reduce @sci.lis -r myrecipelibrary.reduce_nostack

    If you want the cosmic ray rejection, just add the additional steps and remove only the final “p.stackFrames(zero=True)” line.

    #3277

    mschwamb
    Participant

    Thanks Kathleen. Much appreciated. That all worked for me.

    That’s really handy you can write a reicpe to adjust the default one.

    That would be a great tutorial to add about not doing the stacking with that simple recipe. I’ve tried to read all the documentation, but I’m still on the basics. Your explanation was really clear about how to go about it.

    #3278

    mschwamb
    Participant

    Another thing that popped up for me is that the archive images are bz2 zipped when you untar the tarball. I often forget to unbzip2 the files. I would go straight into runnig the dataselect commands.

    It would be nice if DRAGONS could deal with that and bunzip them or give a warning saying that the images are bz2-ed and need to be unzipped.

    Thanks,
    ~Meg

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