The Elixir Team provides master detrend frames as part of the QSO package. The master frames are created using an iterative process. First all the original detrend frames are averaged to create the master. That master is then used to individually flatten the original images creating a residual image. A member of the Elixir team will identify which of these residual images should be included in the master and exclude those that don't belong. This step involves an analysis of the median standard deviation and the clipped standard deviation as well as the general appearance of the flattened detrend image. The process is performed until the Elixir team is satisfied with the resulting master detrend image. These master detrend frames have been used to flatten your science data.
Only the master detrend frames have been provided on this
distribution. The individual flat, bias, and dark frames are NOT included.
The detrend frames follow the naming convention:
The Master Detrend table contains all the information used by elixir for determining which master flat to apply to a science image, primarily the date, filter, and version columns.
Note: A scattered light correction was
applied to the master flats. As a result, the name of the
actual master flats used differs in the