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Using Rspec to Interpret Stellar Spectra

  1. Dec 3, 2011 #1
    Hello, PF.
    I'm a simple high school student who likes a challenge, and as such, I decided to put together a research project involving reading spectral lines from photographs I took. I got the lens, I got the camera, I got pictures, and now I'm stumped. Reading up on Rpsec, a lot of it's users heralded it as "one of the easiest programs to use" for this kind of stuff. Much to my disappointment, it appears the people who said that probably had a more extensive knowledge of the subject than I did when they used it.
    http://filesmelt.com/dl/calibratedimage.png [Broken]
    I've calibrated the image (at least I think I did, if I did something wrong, for the love of all that is good tell me), and I don't know where to go from here.

    If I'm too far over my head and this is a dead end, just tell me and spare the sympathy, I'd rather not waste time with a dead-end project. If it can be done, I implore you to reveal the secret.
     
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Dec 4, 2011 #2

    Drakkith

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    What are you taking pictures of?
     
  4. Dec 4, 2011 #3

    chemisttree

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    try using longer exposures if you can. Is your scope on a tracking mount? You appear to have all that Rspec can give you but the noise is on the same scale as the absorptions you intend to see. You might also try to modify your input data by "stretching" in a program like Photoshop. Play with the contrast, saturation and brightness controls to get as much signal/noise as you can.
     
  5. Dec 4, 2011 #4

    chemisttree

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    Yes, what star are you looking at? You might start by taking a pic of the blue sky through a pinhole or slit and work that up to familarize yourself with Rspec as well.

    edit. based on the filename of HD11506 I'm guessing that he is trying to duplicate the spectral identification of HD11506b by doppler spectrometry.
     
  6. Dec 4, 2011 #5

    chemisttree

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    You might try to mount your grating a little farther from the CCD chip. Mounting it farther away spreads out the spectrum and dims the image a bit. If you do that, you will need to increase your integration time (or decrease your frames/sec if you are using a webcam). Don't forget to use an IR filter for your camera along with your grating (grism?) if the grating itself isn't a good enough IR filter.
     
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