Hot pixel removal

  • Median filter test on the Cd spectrum image at 1.50mm with size=4:
    Cd_1.50_median_filter_size4.png
  • Top images are pre filter, bottom are post filter.
  • Spectrums are the number of photoelectrons as a function of the pixel position
  • Adjusting the size to 1 yields no removal, size = 2 gives mediocre removal and increasing the size past 4 gives no further improvement.

  • Median blur test on the Cd spectrum image at 1.50mm with ksize=3:
    Cd_1.50_medianBlur_size3.png
  • Adjusting the ksize to 1 yields no removal and increasing the ksize past 3 gives no further improvement.

  • Both scipy.ndimage.filters.median_filter and cv2.medianBlur remove hot pixels from this test image with mostly the same result.

  • Median filter test on the 20s dark frame with median_filter size 4:
    DarkFrame_20s_1_median_filter_size4.png

  • Median blur test on the 20s dark frame with ksize=3:
    DarkFrame_20s_1_medianBlur_size3.png

  • Reducing the size and ksize below 4 and 3 respectively yields minimal noise reduction.
  • If removing the hot pixels from the spectrum images works, is processing the dark frames a requirement?

  • Median filter test on the Cd spectrum image at 6.50mm with size 4:
    Cd_6.50_median_filter_size4.png

  • Median blur test on the Cd spectrum image at 6.50mm with ksize=3:
    Cd_6.50_medianBlur_size3.png

  • Testing code on a much brighter section of the spectrum (6.50mm) also shows hot pixel reduction

-- WillBurrows - 13 Oct 2016

Smoothing curves

  • This figure shows a plot of the number of photoelectrons as a function of pixel position, the plots on the top are with the original values, the plots on the bottom are where the average is taken for the 10 adjacent values.
  • Plot for Cd calibration for grating of 0.00mm:
    Cad_plt_0.00.png

  • Calib_cd_0.00.txt: All of the local peaks and its location in the x axis for cad_plt_0.00 plot

  • Calib_cd_6.50.txt: All of the local peaks and its location in the x axis for cad_plt_6.50 plot

  • Calib_cd_10.0.txt: All of the local peaks and its location in the x axis for cad_plt_10.00 plot

  • Plot for clad for grating of 10mm:
    Cad_plot_10.00.png

Topic attachments
I Attachment Action Size Date Who Comment
PNGpng Cad_plot_10.00.png manage 75.0 K 14 Oct 2016 - 13:46 JamesAngthopo Plot for clad for grating of 10mm
PNGpng Cad_plt_0.00.png manage 75.8 K 14 Oct 2016 - 13:28 JamesAngthopo Plot for Cd calibration for grating of 0.00mm
PNGpng Cad_plt_6.50.png manage 53.6 K 14 Oct 2016 - 13:38 JamesAngthopo Plot for Cd calibration for grating of 6.50mm
Texttxt Calib_cd_0.00.txt manage 3.1 K 13 Oct 2016 - 22:48 JamesAngthopo All of the local peaks for cad_plt_0.00 plot
Texttxt Calib_cd_10.0.txt manage 4.3 K 13 Oct 2016 - 22:50 JamesAngthopo All of the local peaks for cad_plt_10.00 plot
Texttxt Calib_cd_6.50.txt manage 3.1 K 13 Oct 2016 - 22:49 JamesAngthopo All of the local peaks for cad_plt_6.50 plot
PNGpng Cd_1.50_medianBlur_size3.png manage 110.2 K 13 Oct 2016 - 17:49 WillBurrows Median blur test on the Cd spectrum image at 1.50mm with ksize=3
PNGpng Cd_1.50_median_filter_size4.png manage 106.6 K 13 Oct 2016 - 17:48 WillBurrows Median filter test on the Cd spectrum image at 1.50mm with size=4
PNGpng Cd_6.50_medianBlur_size3.png manage 61.3 K 13 Oct 2016 - 18:06 WillBurrows Median blur test on the Cd spectrum image at 6.50mm with ksize=3
PNGpng Cd_6.50_median_filter_size4.png manage 61.1 K 13 Oct 2016 - 18:05 WillBurrows Median filter test on the Cd spectrum image at 6.50mm with median_filter size 4
PNGpng DarkFrame_20s_1_medianBlur_size3.png manage 126.3 K 13 Oct 2016 - 17:52 WillBurrows Median blur test on the 20s dark frame with ksize=3
PNGpng DarkFrame_20s_1_median_filter_size4.png manage 127.8 K 13 Oct 2016 - 17:52 WillBurrows Median filter test on the 20s Dark frame with median_filter size 4
Texttxt hot_pixel.py.txt manage 1.4 K 13 Oct 2016 - 18:12 WillBurrows Hot pixel removal test code - python - 20161013
Compressed Zip archivezip plot_figures.zip manage 334.6 K 14 Oct 2016 - 14:07 WillBurrows James' plots

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Topic revision: r6 - 14 Oct 2016 - WillBurrows

 
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