Difference: StewartBoogertPhotometry20171110 (1 vs. 2)

Observation 1

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

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:

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:

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:

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

A row of the above image gives the following

-- BekiChafer - 09 Nov 2017