Calibrating

  • During the week, correct grating position was found and grating was stuck down
  • Sigma of the Gaussian fit to the peak as a function of the lens-camera distance:
    sigma_Distance_Hyperbole.png

  • Hyperbolic function used:
\begin{equation} y = b^2 \sqrt{\frac{x - \mu}{a^2} - 1} \end{equation}
  • Best guess values used are a = 1, b = 4, μ = 21
  • Lowest value of σ is 2.72

  • Sigma of the Gaussian fit to the peak as a function of the camera rotation:
    sigma_Rotation_Cosine.png
  • Cosine function used:
\begin{equation} y = d \times \cos(x + \mu) + \sigma_{\rm{min}} \end{equation}
  • Best guess values used are a = 1, b = 4, μ = 1
  • Lowest value of σ is 3.49
Vega spectrum peak finder

  • Cutoff value = 0.02
  • Size of xrange has to be greater than 2
  • The length of adjacent value considered = 3

  • Plot of normalised Vega spectrum with its normalised second derivative:
    Normalised_plot.png

  • Vega spectrum with its peak located:
    VegaSpec_plot.png
-- WillBurrows - 02 Dec 2016
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I Attachment History Action Size Date Who Comment
PNGpng Normalised_plot.png r1 manage 138.1 K 02 Dec 2016 - 13:42 JamesAngthopo Plot of normalised Vega spectrum with its normalised second derivative
PNGpng VegaSpec_plot.png r1 manage 88.3 K 02 Dec 2016 - 13:43 JamesAngthopo Vega spectrum with its peak located
PNGpng sigma_Distance_Hyperbole.png r1 manage 52.1 K 02 Dec 2016 - 13:35 WilliamBurrows Sigma of the Gaussian fit to the peak as a function of the lens-camera distance
PNGpng sigma_Rotation_Cosine.png r1 manage 48.0 K 02 Dec 2016 - 14:27 WilliamBurrows Sigma of the Gaussian fit to the peak as a function of the camera rotation
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Topic revision: r3 - 02 Dec 2016 - WilliamBurrows

 
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