Note: last week, report segments requested in place of usual weekly update.

Aaron - Image offset parameter investigation: Offset_Parameters.pdf


  • Needed to determine accurate offsets (position and rotation transform) of images.
  • Matched ~30 brightest stars for each image in the Dragonfly cluster (blue filter), comparing to first image in set.
  • Constructed chi-square to compare measured positions in one image to transformed measured positions in offset image.
  • Performed modified least squares fit.
Scaled Errors
  • Error on magnitudes now involves scaling parameters

  • CodeCogsEqn_5.gif
  • where m is the initial magnitude before scaling, c is the intercept in the linear fit (from last meeting) and g is the gradient of the linear fit
  • Laura - m_scaled.pdf

  • Double Cluster HR of a single frame:

  • 96 stars, maximum mag = 13.623

  • Double Cluster HR of a stacked frame:
  • 85 stars, maximum magnitude = 13.300
  • Lower star count in stacked frames possibly due to the stacking of read-out noise in each frame
  • Dragonfly Cluster HR using scaling parameters from the Double Cluster
  • Dragonfly Cluster HR using dragonfly scaling parameters
Topic attachments
I Attachment Action Size Date Who Comment
PDFpdf 210217.pdf manage 1417.0 K 21 Feb 2017 - 21:28 AnishaVadher Real data analysis
GIFgif CodeCogsEqn_5.gif manage 2.0 K 21 Feb 2017 - 21:20 AnishaVadher  
PDFpdf DoubleSingleFrameHR.pdf manage 72.3 K 21 Feb 2017 - 21:06 AnishaVadher Double Cluster HR of a single frame
PNGpng DoubleSingleFrameHR.png manage 48.0 K 21 Feb 2017 - 21:11 AnishaVadher Double Cluster HR of a single frame
PDFpdf DoubleStackedFramesHR.pdf manage 71.6 K 21 Feb 2017 - 21:07 AnishaVadher Double Cluster HR of a stacked frame
PNGpng DoubleStackedFramesHR.png manage 48.4 K 21 Feb 2017 - 21:08 AnishaVadher Double Cluster HR of a stacked frame
PDFpdf Offset_Parameters.pdf manage 104.9 K 20 Feb 2017 - 23:20 AaronAndrews Report segment - offset parameters
PNGpng dragonflyHR_dbclParams.png manage 68.3 K 22 Feb 2017 - 10:53 LauraBevilacqua dragonfly hr with dbcl params
PNGpng dragonflyHR_dragonflyParams.png manage 66.2 K 22 Feb 2017 - 10:54 LauraBevilacqua dragonfly hr with dragonfly params
PDFpdf m_scaled.pdf manage 164.0 K 21 Feb 2017 - 23:22 LauraBevilacqua magnitude scaling with fit parameters, and error

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Topic revision: r5 - 22 Feb 2017 - LauraBevilacqua

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