MDM Observatory 1.3m Telescope Observing Report for 2017 Aug 18

Observer(s): Clarkson, Bord, Vowell, Aufdemberge
Institution(s): UM-Dearborn

Instrument: Andor CCD (Direct Imaging)

Worked for 9.5 hours (all night)
Conditions were Non-Photometric most of the night.
Problems were encountered, see the separate trouble report for details.

Seeing and Weather:
   Clouds all night.
   Beg: Seeing 1.9 arcsec, Cirrus, Winds Light & Variable
   Mid: Seeing 1.9 arcsec, Cirrus, Winds Light & Variable
   End: Seeing 1.9 arcsec, Cirrus, Winds Light & Variable

Observing Summary:

Continued monitoring of V404Cyg primarily in R-band. Observed 
unusual vignetting in CCD field in NE corner which changed in
structure and size, eventually covering over half the 
field and then abruptly disappeared.  Sequence of images will
be provided documenting phenomena.  Once the field cleared, no
obvious problems were encountered with the telescope or detector
systems, save with ending flats where structure was again seen 
resembling spider legs. Night also included observations of 
VV Cep primarily in U, along with UBV standard star measures. 
See trouble report for more.

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Submitted on 2017 Aug 19 [5:43:25]