Science Imaging

I am off to sleep.

Willie

I was plotting relative values for all of the stars, so any variation in one would affect the others. Here is a new plot with just the target plotted as a relative value, the comparisons are plotted as Source-background. It shows that the comps are not varying. This is a better plotcfg for this type run.

Willie

According to this AAVSO finder chart, those should be good comparisons.

Willie

Good question, Dick. I noticed that but didn’t try to resolve it.

I thought it was because I let them get too close to the edge of the frame or that it was due to variation in the background. Sometimes when you have faint comps and there is significant variation in the background (like when the moon was coming up and the background brightened significantly) it affects the fainter ones more dramatically than the brighter ones. That will cause one to increase and the other to decrease the same amount.

But perhaps the first 2 do do vary over a longer time frame. Later today, I will look at it using different comps and see if it is any different.

Willie


> On Oct 22, 2016, at 8:00 AM, Science Imaging <science-imaging@centexastronomy.org> wrote:
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> Why do your comps look like they are variable?
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Here is the field of view showing the comparisons as an attachment so it can be viewed at higher resolution.

Here is the light curve as an attachment so it can be viewed at higher resolution.