On the night of Nov 12/13, 2021, under fair and then poor conditions, I acquired images of the eclipsing binary system WZ Cyg as part of a capstone project.
I had to wait for early clouds to disappear, then had two hours of clear skies. After that, broken clouds came and went, permitting some measurements for the next three hours.
The main setup was:
Notes from the night:
The object is located at
RA = 20:53:06.78 Dec = +38 49 40.7 (J2000)
A chart of the field is shown below. The size of the chart is about 31 x 26 arcminutes.
I've marked the location of several comparison stars as well. The bright star P is the ninth-magnitude HD 198975.
I'll use star "A" to shift my instrumental magnitudes to the V-band scale.
I took a photo of the finder TV's screen when pointing to this target; this could be a useful reference for the future:
The sky value shows mostly clear early, but mostly cloudy later.
The FWHM graph below shows a jump when I modified the focus position, then gradual increase due to cooling and increased airmass.
Using aperture photometry with a radius of 10 pixels in B and V filters (binned 2x2, each pixel is 1.24 arcsec, so a radius of 12.4 arcsec), I measured the instrumental magnitudes of a number of reference stars and the target. Following the procedures outlined by Kent Honeycutt's article on inhomogeneous ensemble photometry, I used all stars available in each image to define a reference frame, and measured each star against this frame.
Sigma-vs-mag plots show that the floor was about 0.009 mag in B, 0.008 in V.
The change in zeropoint shows lots of cloudy periods.
Last modified 10/13/2021 by MWR.