Data products and analysis overview

Data product types

Non-redundant masking - The data reduction process will produce [differential] visibilities and closure-phases from the raw interferograms. These resulting data products, and how to read them with supplied Python tools, are described here (work-in-progress).
Full-puil imaging (a.k.a. speckle imaging) - the raw data files contain interleaved frames of orthogonal polarisations distributed between several files. For ease-of-use, an 'untangled' version of these files can be provided, and are labelled as follows:
```
  [target name]_[description string]_[serial number]_[chan]_[FLC].fits
```
where [target name]_[description string] will be something like "alfCen_01_20170130_750_Fullpupil". the "_01" identifies which sets of observations of this target (as detailed in observing logs). [serial number] corresponds to the file number of the original data (usually starting at 0 and counting up), [chan] is the beamsplitter channel (i.e. which camera), labelled as '1' or '2' and [FLC] is the FLC state, labelled as 'A' or 'B'. Data is in the standard VAMPIRES half-wave plate acquisition sequence, i.e. the first file is HWP=0, the second file is HWP=22.5, then 45, then 67.5, then back to 0. Each file will have _1_A, _1_B, _2_A and _2_B variants.
Spectral differential (Hα, etc.) - Currently the raw files are provided, as the format is straightforwards. Filename format is as follows:
```
  [target name]_HaDifferential-[state]_[description string]_[serial number]_[chan].fits
```
where [target name] will be something like "alfCen_01", [state] (either "state1" or "state2") indicates which state the differential filter pair are in, [serial number] corresponds to the file number of the original data (usually starting at 0 and counting up), and [chan] (either "cam1" or "cam2") indicates which camera this data is from.
- For Hα,
  - state1: cam1 = continuum, cam2 = Hα
  - state2: cam1 = H&alpha, cam2 = continuum;
- Files with contiguous numbers in [target name] (e.g. "alfCen_01", "alfCen_02", ...) may be a single data set, with breaks in numbers simply being when acquisition was interrupted for some reason. Refer to observing logs.
- The last file in each set may include empty frames at the end, since the cube-length is constant.
- Note that Hα mode is still in development, so the FITS headers of these data are not very complete.
- IMPORTANT: The first frame in each cube is a junk frame and should be discarded!

TODO:

Include complete documentation on data products, etc.* For now:

The original NRM-mode data documentation is here (with improper syntax highlighting).

The Python code described therein can be downloaded here.