-- LauraBevilacqua - 14 Oct 2016

MEETING 1: 14/10/2016

-Reverse grayscale as black dots easier to see on white background

-Pixel Values set from 0-max pixel value of the image

-Bright pixels clearly seen

  • Dark Frame at 300s exposure:
    DarkFrame300max55000.jpg

  • Dark Frame at 300s exposure, maximum value set to the image median multiplied by 2: DarkFrame300maxmedian2.jpg
-RGB colour space used to define pixel colour so: black=(0,0,0), white=(255,255,255)

-Fill function scans for black pixels and finds adjacent black pixels, fills them red

-Counting begins when black pixel is found

-Function returns number of stars and coordinate of brightest pixel

MEETING 2: 21/10/2016

  • Fits files from Aaron converted to monochrome images

  • Image of single star
    FinderTest1a.jpg
  • The maximum pixel value was found to be 65195 from the fits file, as opposed to Aaron's given value of 65535
  • 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
  • Program locates star and returns count of 1
FinderTest1a_count.png

  • Image of 8 stars
    FinderTest3.jpg

  • Maximum pixel value found to be 62673, compared to Aaron's 60000
  • Threshold set as 20 so that stars don't touch, achieves accurate count of 8
    FinderTest3_mon.jpg
  • FinderTest3_count.png
Topic attachments
I Attachment History Action Size Date Who Comment
JPEGjpg DarkFrame300max55000.jpg r1 manage 53.2 K 14 Oct 2016 - 11:57 LauraBevilacqua Dark Frame at 300s exposure
JPEGjpg DarkFrame300maxmedian2.jpg r1 manage 58.1 K 14 Oct 2016 - 11:58 LauraBevilacqua Dark Frame at 300s exposure, maximum value set to the image median multiplied by 2
JPEGjpg FinderTest1a.jpg r1 manage 6.5 K 20 Oct 2016 - 13:59 LauraBevilacqua  
PNGpng FinderTest1a_count.png r1 manage 12.8 K 20 Oct 2016 - 14:06 LauraBevilacqua  
JPEGjpg FinderTest1a_mon.jpg r1 manage 5.4 K 20 Oct 2016 - 13:59 LauraBevilacqua  
JPEGjpg FinderTest3.jpg r1 manage 14.1 K 20 Oct 2016 - 13:59 LauraBevilacqua  
PNGpng FinderTest3_count.png r1 manage 15.5 K 20 Oct 2016 - 14:45 LauraBevilacqua  
JPEGjpg FinderTest3_mon.jpg r1 manage 6.2 K 20 Oct 2016 - 13:59 LauraBevilacqua  
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Topic revision: r2 - 20 Oct 2016 - LauraBevilacqua

 
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