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Detecting hot pixels We had two 1 hour exposure dark frames. One was at an angle and the other pointed upwards. We wanted to find the x and y coordinates...
Improving Hot Pixel Detection Algorithm Set out to create an improved algorithm for detecting hot pixels, Set out to create a 3 by 3 pixel square which traces...
People present at start: David Hadden, Elena Cukanovaite, Professor Stewart Boogert. Ian Connelly joined later. Before taking data Time of turn on: 18.20....
Images We chose the Alpha Persei cluster (Cr 39) to look at, but as it is a large cluster, we took images of two different sections of it, example images of which...
Improvements Following on from last weeks meeting, it was suggested the colourmaps used were not overly clear. A version with better contrast has been chosen...
Floodfill algorithm improvements To improve our algorithm we defined a star to be anything above 5 pixels in size. It seems that all hot pixels were removed...
Mode Substraction We substracted the split mode image from the original image. If one performs mode split on the resulting image, one gets 0 for the mode...
Temperature Control for CCD We first tested the lowest temperature we could achieve for the CCD, whilst keeping the cooler power at around 90%, so that small changes...
Histogram of the trial image The trial images is shown below. The histogram is done over the entire trial image and is divided into 50 bins. The bin with the most...
From SBIG manuals: During readout of a pixel, the charge in a pixel is stored in a capacitor temporarily. After readout, the capacitor is drained and the next...
Initial histogram The dark frames were analysed by plotting a histogram of all the photoelectron values. However, specifying too many bins will mean that some of the...
test DavidHadden 20 Oct 2015
Initial Investigations Whilst the camera was cooling we attempted to take light frames (pointed at a roughly uniform section of the inside of the dome) in order to...
Theory In a CCD the signal is measured in terms of the charge that is stored on to each pixel, however in converting this charge into a signal, the number of ADUs...
Comparing stars between different filters In order to compare the quality of our data, we looked at the data with the largest signal to noise ratio, in this case...
Mode vs. Median Background The problem with using the mode is that if a number does not appear more than once then the mode just takes the first number in the...
Goodness of fit with maximum likelihood progress Curve fit fitting used the following equation: \begin{equation} f(x,y,\mu x,\mu y,\sigma x,\sigma y,\rho,a,d...
Checking fit validity p values give a probability, so should be normalised to 1. Found p value for each pixel, and summed over all pixels Found summed...
DavidHadden 03 Feb 2016
ElenaCukanovaite 10 Feb 2016
Comparison of fits Before we fitted an unskewed Gaussian: \begin{equation} f G(x,y,\mu x,\mu y,\sigma x,\sigma y,\rho, \beta 1, \beta 2) \frac{1}{2\pi\sigma...
Testing the fitting First we wanted to test that the function we are fitting is actually normalised. The skewed Gaussian function is: \begin{equation} f...
MLE H R diagram B V: V R: Aperture photometry H R B V: V R: Error analysis Generated 1000 stars, fitted them to get the errors. Found...
Measuring master frames In order to build up a catalogue of master dark, bias and flat frames... Began by taking bias, dark and flat frames shortly after beginning...
2015 Projects Photometry Spectroscopy 2016 Projects Photometry Spectroscopy 2017 Projects 2018 Projects Photometry 2019 Projects...
Number of topics: 25
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