Difference: StewartBoogertPhotometry20161202 (1 vs. 6)

Revision 602 Dec 2016 - AaronAndrews

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META TOPICPARENT name="StewartBoogertPhotometry2016"
-- AaronAndrews - 01 Dec 2016
Line: 38 to 38
 
  • Fit a gaussian to the truncated histogram, the mean of the gaussian corresponds to the mode of the truncated data
  • If there are not enough bins (less than 25), fit may not be executed, therefore we estimate the mode by finding the bin with the maximum frequency, return single value of mode
  • Run mode filter using output from truncation algorithm to obtain an array of modal pixel values
Added:
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  • M103_Mode_full.png
 
META FILEATTACHMENT attachment="Obs2_images_stacked.zip" attr="" comment="Observation2 - stacked images" date="1480585482" name="Obs2_images_stacked.zip" path="Obs2_images_stacked.zip" size="20631280" user="zyva010" version="1"
META FILEATTACHMENT attachment="DoubleCluster_200s_blue_5stack.png" attr="" comment="Double Cluster (blue) stacked" date="1480585984" name="DoubleCluster_200s_blue_5stack.png" path="DoubleCluster_200s_blue_5stack.png" size="1100020" user="zyva010" version="1"
Line: 50 to 51
 
META FILEATTACHMENT attachment="M103_VIS_60S.png" attr="" comment="M103 - real image" date="1480637219" name="M103_VIS_60S.png" path="M103_VIS_60S.png" size="1569987" user="zyva010" version="1"
META FILEATTACHMENT attachment="M103_Simtest_BG_2.txt" attr="" comment="median background fit - parameters" date="1480637260" name="M103_Simtest_BG_2.txt" path="M103_Simtest_BG_2.txt" size="682" user="zyva010" version="1"
META FILEATTACHMENT attachment="M103_Simtest_BG_3.txt" attr="" comment="direct background fit - parameters" date="1480637279" name="M103_Simtest_BG_3.txt" path="M103_Simtest_BG_3.txt" size="681" user="zyva010" version="1"
Added:
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META FILEATTACHMENT attachment="M103_Mode_full.png" attr="" comment="M103 sim. - mode for whole frame" date="1480684255" name="M103_Mode_full.png" path="Y:\PH4100\Simulation\M103_Mode_full.png" size="30972" user="zyva010" version="1"

Revision 502 Dec 2016 - LauraBevilacqua

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META TOPICPARENT name="StewartBoogertPhotometry2016"
-- AaronAndrews - 01 Dec 2016
Line: 31 to 31
 
  • LEFT: Median filter for M103. RIGHT: taylor series fit (25 terms, origin=(0,0))
  • M103_Median_65box.pngM103_Simtest_BGmean_2.png
  • Attempted to fit up to 100 terms - failed.
Added:
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Truncated Histogram:
  • Aim to make a mode filter over an image by defining a function that returned the mode of a truncated histogram
  • Stars populate the tail of the histogram with low frequencies --> set threshold frequency for mode filter as 1000/((1530*1020)/65^2) = 2
  • The mode is the pixel value with the highest frequency
  • Fit a gaussian to the truncated histogram, the mean of the gaussian corresponds to the mode of the truncated data
  • If there are not enough bins (less than 25), fit may not be executed, therefore we estimate the mode by finding the bin with the maximum frequency, return single value of mode
  • Run mode filter using output from truncation algorithm to obtain an array of modal pixel values
 
META FILEATTACHMENT attachment="Obs2_images_stacked.zip" attr="" comment="Observation2 - stacked images" date="1480585482" name="Obs2_images_stacked.zip" path="Obs2_images_stacked.zip" size="20631280" user="zyva010" version="1"
META FILEATTACHMENT attachment="DoubleCluster_200s_blue_5stack.png" attr="" comment="Double Cluster (blue) stacked" date="1480585984" name="DoubleCluster_200s_blue_5stack.png" path="DoubleCluster_200s_blue_5stack.png" size="1100020" user="zyva010" version="1"

Revision 402 Dec 2016 - AaronAndrews

Line: 1 to 1
 
META TOPICPARENT name="StewartBoogertPhotometry2016"
-- AaronAndrews - 01 Dec 2016
Line: 25 to 25
 %ENDLATEX%
  • In order to get parameters, set up code to do a fit over an array of values using the expansion, up to a set number of terms.
  • First applied fit directly to image of M103 from observation 1, up to 25 terms:
Changed:
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  • LEFT: original image, M103. RIGHT: taylor series fit (25 terms)
>
>
  • LEFT: original image, M103. RIGHT: taylor series fit (25 terms, origin=(0,0))
 
  • M103_VIS_60S.pngM103_Simtest_BGmean_3.png
  • Then applied median analysis to frame first, then attempted fit (25 terms):
Changed:
<
<
  • LEFT: Median filter for M103. RIGHT: taylor series fit (25 terms)
>
>
  • LEFT: Median filter for M103. RIGHT: taylor series fit (25 terms, origin=(0,0))
 
  • M103_Median_65box.pngM103_Simtest_BGmean_2.png
  • Attempted to fit up to 100 terms - failed.

Revision 302 Dec 2016 - AaronAndrews

Line: 1 to 1
 
META TOPICPARENT name="StewartBoogertPhotometry2016"
-- AaronAndrews - 01 Dec 2016
Line: 6 to 6
 
  • Observation 2: 20161125
  • Took multiple luminous, red, visual, and blue frames of Double Cluster and Dragonfly Cluster.
  • Used guide scope to control star tracking. Therefore, could stack frames.
Changed:
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<
  • Example: Double cluster, blue, total exposure time (for 5 frames) 200s:
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>
  • Example: Double cluster, blue, total exposure time (for 5 frames) 200s - more stars visible:
 
  • DoubleCluster_200s_blue_5stack.png
Changed:
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  • Uplaoded all stacked frames to astrometry.net to fit (excluding blue for Dragonfly - guide system was not set up correctly when taking frames):
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>
  • Uplaoded all stacked frames to astrometry.net to fit:
 
Added:
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Changed:
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  • Filter RA DEC
    Double Cluster blue
    visual 02h 22m 05.818s +57 11' 11.674"
    red
    Dragonfly Cluster visual
    red
>
>
  • Filter RA DEC
    Double Cluster blue 02h 22m 06.252s +57 11' 05.203"
    visual 02h 22m 05.818s +57 11' 11.674"
    red 02h 22m 05.973s +57 11' 10.444"
    Dragonfly Cluster blue 01h 19m 21.635s +58 21' 26.031"
    visual 01h 19m 29.901s +58 21' 01.003"
    red 01h 19m 26.550s +58 21' 11.465"
Simulation: Simulation_test11.py.txt

  • Can generate background mean (or standard deviation) using taylor series:
 \begin{equation} f\left ( x;a_{ij} \right ) = \sum_{i=0}^{N_{i}} \sum_{j=0}^{N_{j}} \frac{a_{ij}}{i!j!} \left ( x-x_{0} \right )^{i} \left ( y-y_{0} \right )^{j} \end{equation}
  • In order to get parameters, set up code to do a fit over an array of values using the expansion, up to a set number of terms.
  • First applied fit directly to image of M103 from observation 1, up to 25 terms:
  • LEFT: original image, M103. RIGHT: taylor series fit (25 terms)
  • M103_VIS_60S.pngM103_Simtest_BGmean_3.png
  • Then applied median analysis to frame first, then attempted fit (25 terms):
  • LEFT: Median filter for M103. RIGHT: taylor series fit (25 terms)
  • M103_Median_65box.pngM103_Simtest_BGmean_2.png
  • Attempted to fit up to 100 terms - failed.
 
META FILEATTACHMENT attachment="Obs2_images_stacked.zip" attr="" comment="Observation2 - stacked images" date="1480585482" name="Obs2_images_stacked.zip" path="Obs2_images_stacked.zip" size="20631280" user="zyva010" version="1"
META FILEATTACHMENT attachment="DoubleCluster_200s_blue_5stack.png" attr="" comment="Double Cluster (blue) stacked" date="1480585984" name="DoubleCluster_200s_blue_5stack.png" path="DoubleCluster_200s_blue_5stack.png" size="1100020" user="zyva010" version="1"
Added:
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META FILEATTACHMENT attachment="Simulation_test11.py.txt" attr="" comment="Simulation code (11)" date="1480633547" name="Simulation_test11.py.txt" path="Simulation_test11.py" size="32740" user="zyva010" version="1"
META FILEATTACHMENT attachment="latexa0be1fc22480ab7e803cf0b055b2df78.png" attr="h" comment="" date="1480635429" name="latexa0be1fc22480ab7e803cf0b055b2df78.png" user="zyva010" version="1"
META FILEATTACHMENT attachment="M103_Simtest_BGmean_2.png" attr="" comment="Background mean using median" date="1480636752" name="M103_Simtest_BGmean_2.png" path="M103_Simtest_BGmean_2.png" size="102996" user="zyva010" version="1"
META FILEATTACHMENT attachment="M103_Simtest_BGmean_3.png" attr="" comment="Background mean using raw image" date="1480636773" name="M103_Simtest_BGmean_3.png" path="M103_Simtest_BGmean_3.png" size="135347" user="zyva010" version="1"
META FILEATTACHMENT attachment="M103_Simtest_starsBG_3.fits" attr="" comment="M103 simulation plus background directly from real image" date="1480637014" name="M103_Simtest_starsBG_3.fits" path="M103_Simtest_stars+BG_3.fits" size="12487680" user="zyva010" version="1"
META FILEATTACHMENT attachment="M103_Median_65box.png" attr="" comment="M103 median" date="1480637017" name="M103_Median_65box.png" path="M103_Median_65box.png" size="95116" user="zyva010" version="1"
META FILEATTACHMENT attachment="M103_VIS_60S.png" attr="" comment="M103 - real image" date="1480637219" name="M103_VIS_60S.png" path="M103_VIS_60S.png" size="1569987" user="zyva010" version="1"
META FILEATTACHMENT attachment="M103_Simtest_BG_2.txt" attr="" comment="median background fit - parameters" date="1480637260" name="M103_Simtest_BG_2.txt" path="M103_Simtest_BG_2.txt" size="682" user="zyva010" version="1"
META FILEATTACHMENT attachment="M103_Simtest_BG_3.txt" attr="" comment="direct background fit - parameters" date="1480637279" name="M103_Simtest_BG_3.txt" path="M103_Simtest_BG_3.txt" size="681" user="zyva010" version="1"

Revision 201 Dec 2016 - AaronAndrews

Line: 1 to 1
 
META TOPICPARENT name="StewartBoogertPhotometry2016"
-- AaronAndrews - 01 Dec 2016
Line: 8 to 8
 
  • Used guide scope to control star tracking. Therefore, could stack frames.
  • Example: Double cluster, blue, total exposure time (for 5 frames) 200s:
  • DoubleCluster_200s_blue_5stack.png
Changed:
<
<
*
>
>
 
META FILEATTACHMENT attachment="Obs2_images_stacked.zip" attr="" comment="Observation2 - stacked images" date="1480585482" name="Obs2_images_stacked.zip" path="Obs2_images_stacked.zip" size="20631280" user="zyva010" version="1"
META FILEATTACHMENT attachment="DoubleCluster_200s_blue_5stack.png" attr="" comment="Double Cluster (blue) stacked" date="1480585984" name="DoubleCluster_200s_blue_5stack.png" path="DoubleCluster_200s_blue_5stack.png" size="1100020" user="zyva010" version="1"

Revision 101 Dec 2016 - AaronAndrews

Line: 1 to 1
Added:
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META TOPICPARENT name="StewartBoogertPhotometry2016"
-- AaronAndrews - 01 Dec 2016

Observation on 25/11/2016:

  • Observation 2: 20161125
  • Took multiple luminous, red, visual, and blue frames of Double Cluster and Dragonfly Cluster.
  • Used guide scope to control star tracking. Therefore, could stack frames.
  • Example: Double cluster, blue, total exposure time (for 5 frames) 200s:
  • DoubleCluster_200s_blue_5stack.png *

META FILEATTACHMENT attachment="Obs2_images_stacked.zip" attr="" comment="Observation2 - stacked images" date="1480585482" name="Obs2_images_stacked.zip" path="Obs2_images_stacked.zip" size="20631280" user="zyva010" version="1"
META FILEATTACHMENT attachment="DoubleCluster_200s_blue_5stack.png" attr="" comment="Double Cluster (blue) stacked" date="1480585984" name="DoubleCluster_200s_blue_5stack.png" path="DoubleCluster_200s_blue_5stack.png" size="1100020" user="zyva010" version="1"
 
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