Difference: 20151101_MSciSpectrocopyLab (1 vs. 2)

• Analysed a two dark frames to find locations of hot pixels. 1st Dark frame had a 1 second exposure time at a temperature of 20 degrees. 2nd Dark frame had a second exposure time at a temperature at 5 degrees.
• As can be seen from both spectrums below, the 2nd dark frame has comparatively less background fluctuations due to the lower temperature.
• A code was written to print the index of the pixel values which exceed the mean+standard deviation of the 1D array obtained from summing each column of pixels downwards. Pixel values exceeding this limit are considered signicantly above the background.
• Spectrum of dark frame analysed with spikes indicating hot pixels:

• Pixel values exceeding this limit were located at pixel positions 90, 180, 222, 407, 490, 497, 617 along the x axis for the 1st dark frame.
• Pixel values exceeding this limit were located at positions 90, 222, 407, 617 along x axis for 2nd dark frame - conclude these are hot pixels.

• After meeting on 28/10/15, decided to fit a hyperbole to the standard deviation against focus distance plot and a sine function to the standard deviation against camera angle plot - these fits were a much better fit than the parabolas.
• Chi square value for focus = 0.00665
• Chi square value for angle = 0.000382
• Still need to adjust errors - will ask Prof Cowan in own time

-- AshleaKemp - 02 Nov 2015