Observation 1

We took two images of the double cluster: NGC869, NGC884, with two different cameras, with different fields of view.

NarrowFieldView_4s_dc869.png widefield_15s_dc869.png

Star Simulation

Main aim this week: background fluctuations

From the larger image, you can see that there is a fluctuation in the background biased towards the left of the image.
Image below is the larger image with a high contrast:

BgBiasExample.png

To account for this bias, the image was analysed row by row. Taking a random row of the image and plotting the value with the column number, you get:

Fitting_Background_to_use_for_simulation.png

The majority of this is background, the spikes are stars. Then, I fit a 2d polynomial to the data. This was repeated for every row, and the parameters for the fit were averaged. This gave me the following function:

Average_background_of_Image_left_to_right_-_use_for_simulation.png

This was then used to add background fluctuations to images, poisson fluctuations also implemented.

TestbgLarge.png

A row of the above image gives the following

Background_of_Simulated_image.png

-- BekiChafer - 09 Nov 2017

Topic attachments
I Attachment History Action Size Date Who Comment
PNGpng Average_background_of_Image_left_to_right_-_use_for_simulation.png r1 manage 29.1 K 09 Nov 2017 - 22:33 RebekahChafer1  
PNGpng Background_of_Simulated_image.png r1 manage 32.9 K 09 Nov 2017 - 22:42 RebekahChafer1  
PNGpng BgBiasExample.png r1 manage 7016.1 K 09 Nov 2017 - 22:25 RebekahChafer1 High Contrast Image to show bg bias
PNGpng Fitting_Background_to_use_for_simulation.png r1 manage 39.3 K 09 Nov 2017 - 22:30 RebekahChafer1  
PNGpng NarrowFieldView_4s_dc869.png r1 manage 448.6 K 09 Nov 2017 - 14:01 RebekahChafer1 Narrow Field Image
PNGpng TestbgLarge.png r1 manage 9891.5 K 09 Nov 2017 - 22:36 RebekahChafer1  
PNGpng widefield_15s_dc869.png r1 manage 13704.4 K 09 Nov 2017 - 14:02 RebekahChafer1 Wide Field Image
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Topic revision: r2 - 09 Nov 2017 - RebekahChafer1

 
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