Focusing the camera

  • Focused the camera by changing focal length between lens and camera.
  • Cut-off value: $-0.06$, for all values
  • x range: $x_2 -x_1 < 2$.
  • Obtained $\sigma$ values for different focal length using algorithm
Focal length (mm) 20.00 20.50 21.00 21.50 21.69 22.00 22.50 23.00
Sigma value 5.08659093449 2.8121312033 2.71009808794 2.67484736244 3.65774734138 6.14996469992 5.67972147 5.704260238

  • Obtained $\sigma$ values for different focal length using ImageJ
Focal length (mm) 20.00 20.50 21.00 21.50 21.69 22.00 22.50 23.00
Sigma value 9.342539803 5.945252602 3.82194101 3.397287201 3.821948101 5.095930802 8.493218003 13.5891488

  • Plot showing sigma as a function of focal length:
    Focallengthplot.png

  • Standard deviation of the Gaussian fits to the peak as a function of the focal length:
    sigma_focal_length.png

  • Obtain $\sigma$ values for different rotation of camera obtained using peak finder
Rotation (mm) 2.00 2.50 3.00 3.21 3.50 4.00 4.50 5.00
Sigma values 3.60381891499 3.63753847945 4.56762848828 3.64517768764 3.60828884108 3.74669667918 3.65238841404 4.74355676159

  • Obtain $\sigma$ for different rotation of camera obtained using ImageJ
Rotation (mm) 2.00 2.50 3.00 3.21 3.50 4.00 4.50 5.00
Sigma values 3.39728720 4.246609001 3.397287201 3.821948101 3.821948101 4.246609001 3.821948101 3.821948101

Peak asymmetry

  • Grating is centered on the mount, orientation of the blaze arrow is changed to investigate the asymmetry of the peak shape at different positions across the grating
  • Peak chosen is a bright line in He at a large grating angle (micrometer setting)

  • Asymmetry of the peak for different pixel positions, with the blaze arrow pointed away from the camera:
    peak_asymmetry_away.png

  • Asymmetry of the peak for different pixel positions, with the blaze arrow pointed towards the camera:
    peak_asymmetry_toward.png
-- JamesAngthopo - 25 Nov 2016
Attachments Attachments
Topic attachments
I Attachment History Action Size Date Who Comment
PNGpng Focallengthplot.png r1 manage 96.5 K 25 Nov 2016 - 12:23 JamesAngthopo Plot of change in sigma against change in focal length
Texttxt Peakfinder.txt r1 manage 4.7 K 25 Nov 2016 - 13:59 JamesAngthopo Code for peak finder
Texttxt asymmetry.py.txt r1 manage 1.5 K 25 Nov 2016 - 12:10 WilliamBurrows Code to display the peak asymmetry
Texttxt focus_curves.py.txt r1 manage 2.0 K 25 Nov 2016 - 13:58 WilliamBurrows Code to plot standard devtiations as a function of micrometer settings
PNGpng peak_asymmetry_away.png r1 manage 52.2 K 25 Nov 2016 - 11:57 WilliamBurrows Asymmetry of the peak for different pixel positions, with the blaze arrow pointed away from the camera
PNGpng peak_asymmetry_toward.png r1 manage 57.8 K 25 Nov 2016 - 11:58 WilliamBurrows Asymmetry of the peak for different pixel positions, with the blaze arrow pointed towards the camera
PNGpng sigma_focal_length.png r2 r1 manage 26.3 K 25 Nov 2016 - 13:55 WilliamBurrows Standard deviation of the Gaussian fits to the peak as a function of the focal length

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Topic revision: r7 - 25 Nov 2016 - JamesAngthopo

 
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