Difference: StewartBoogertPhotometry20161021 (8 vs. 9)

Revision 921 Oct 2016 - AnishaVadher

Line: 1 to 1
 
META TOPICPARENT name="StewartBoogertPhotometry2016"
-- LauraBevilacqua - 18 Oct 2016
Line: 19 to 19
  Anisha:
Changed:
<
<
  • Corrected histrogram of number of photoelectrons for a 0.1s exposure in the dark frame with 500 bins - logarithmicly normalized:
    Histogram_of_number_of_pixel_values_for_0.1s_exposure_500_bins.png
>
>
  • Corrected histrogram of number of photoelectrons for a 0.1s exposure in the dark frame with 500 bins - logarithmicly normalized:
    Histogram_of_number_of_pixel_values_for_0.1s_exposure_500_bins.png
 
Changed:
<
<
  • The median intensity as a function of exposure time.:
    The_median_intensity_as_a_function_of_exposure_time_with_best_fit.png
>
>
  • The median intensity as a function of exposure time.:
    The_median_intensity_as_a_function_of_exposure_time_with_best_fit.png
 
  • Line of best fit: y = 917.43 + 0.08x
Changed:
<
<
  • Error as a function of exposure time:
    Error_as_a_function_of_exposure_time_with_best_fit.png
>
>
  • Error as a function of exposure time:
    Error_as_a_function_of_exposure_time_with_best_fit.png
 
  • Line of best fit: y = 15.76 + 0.73x
%BEGINLATEX% Mean number of effective photoelectrons : \begin{equation} \nu = \nu_0 + \mu t. \end{equation} Actual number of photoelectrons: \begin{equation} n = n_0 + m, \end{equation} where $n_0$ follows a Gaussian distribution and may come from electronic noise and $m$ follows a Poisson distribution as a function of $\mu t$. Error in $m \sigma_m$ come from $\sqrt{\mu t}$.
Line: 60 to 60
 
  • Images scanned for stars and correct star count is returned
  • Edge detection helps identify star position
Changed:
<
<
  • The maximum pixel value was found to be 65195 from the fits file below, as opposed to Aaron's given value of 65535
    FinderTest1a.jpg
  • Threshold of 100 set so if pixels are above this value they are set as white background, if below they are coloured black (remember reverse grayscale):
    FinderTest1a_mon.jpg
  • Edge detection:
    FinderTest1a_count.png
>
>
  • The maximum pixel value was found to be 65195 from the fits file below, as opposed to Aaron's given value of 65535
    FinderTest1a.jpg
  • Threshold of 100 set so if pixels are above this value they are set as white background, if below they are coloured black (remember reverse grayscale):
    FinderTest1a_mon.jpg
  • Edge detection:
    FinderTest1a_count.png
 
Changed:
<
<
  • Maximum pixel value found to be 62673, compared to Aaron's 60000:
    FinderTest3.jpg
  • Threshold set as 20 so that stars don't touch, achieves accurate count of 8:
    FinderTest3_mon.jpg
    FinderTest3_count.png
>
>
  • Maximum pixel value found to be 62673, compared to Aaron's 60000:
    FinderTest3.jpg
  • Threshold set as 20 so that stars don't touch, achieves accurate count of 8:
    FinderTest3_mon.jpg
    FinderTest3_count.png
 
META FILEATTACHMENT attachment="SkewTest2.png" attr="" comment="Testing x and y correlation (P) for P=0, P=0.5, P=0.999" date="1476827216" name="SkewTest2.png" path="SkewTest2.png" size="19013" user="zyva010" version="1"
META FILEATTACHMENT attachment="Histogram_of_number_of_pixel_values_for_0.1s_exposure_500_bins.png" attr="" comment="Corrected histrogram of number of photoelectrons for a 0.1s exposure in the dark frame with 500 bins - logarithmicly normalized" date="1476982418" name="Histogram_of_number_of_pixel_values_for_0.1s_exposure_500_bins.png" path="Histogram_of_number_of_pixel_values_for_0.1s_exposure_500_bins.png" size="18847" user="zyva858" version="1"
 
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