Difference: 20151208MSciPhotometryAnalysisOb1part4 (11 vs. 12)

Revision 1208 Dec 2015 - ElenaCukanovaite

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META TOPICPARENT name="StewartBoogertPhotometry2015"

Mode Substraction

  • We substracted the split mode image from the original image.
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b_r.png
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b_r.png
 
  • The above graph is an example of a fitted star for summed rows. This appeared to be a good fit, although a slight skew appears to exist in this data, so we modified our fitting function in order to account for this, by changing the y term in the formula to a polynomial in y. (visible skew in y, not so much in x, left it for now).
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  • This was then performed, and a comparison can be seen below:
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skewed_example.png
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skewed_example.png
 
  • From this, one can see that this seems to follow the points better, but not perfectly, and highlights the skew of the curve.
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  • It appears however that most stars summed columnly are not skewed as can be seen below:
equal.png
 
  • However, not all fits were so successful.

Fitting problems

  • A recurring issue seen in our projections is the presence of more than 1 star in the cropped image, which obviously does not fit properly.
  • This is currently a major issue for such scenarios, which must be resolved.
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  -- ElenaCukanovaite - 08 Dec 2015
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