ImageCalibration: Improved CFA Data Management
The following new parameters are used by the ImageCalibration process to modify its behavior for calculation of master dark frame optimization factors and master flat scaling factors:
* New Enable CFA parameter. Enable this option to support data acquired with digital cameras that generate images mosaiced with a Color Filter Array (CFA). Bayer and X-Trans CFAs are supported. When this option is selected, the CFA pattern can be selected with the CFA mosaic pattern parameter (see below). You normally should leave that parameter with its default Auto selection, which should detect the correct pattern automatically under normal working conditions.
* New CFA mosaic pattern parameter. This is the CFA pattern of the camera (such as a DSLR or OSC camera) used to acquire the calibration master and target frames. The Auto option uses view properties that can be available in the master and target frame files. Under normal working conditions, these properties are either generated automatically by the RAW format support module and stored in XISF files, or available as FITS header keywords in the case of raw OSC frames. For non-CFA data acquired with monochrome CCD or CMOS cameras, the Auto option is the correct selection because in these cases the process will detect no CFA pattern automatically. For images acquired with X-Trans sensors this parameter is ignored and CFA patterns are always extracted from existing image properties.
* New Separate CFA flat scaling factors parameter. When this option is enabled and the master flat frame is a single-channel image mosaiced with a Color Filter Array (CFA), such as a Bayer or X-Trans filter pattern, three separate master flat scaling factors are computed for the red, green and blue CFA components, respectively. When this option is disabled, a single scaling factor is computed for the whole master flat frame, ignoring CFA components (which has been the behavior of ImageCalibration until the 1.8.8-6 release).