Dark Current Subtraction
Description
The step DarkSubtractionStep
subtracts a dark reference image from an input image.
Algorithm
The SCI array from the dark reference file is subtracted from the SCI array of the science data set, and the dark DQ array is combined with the science DQ array using a bit-wise OR operation. The science ERR array is updated by adding the science and dark ERR arrays in quadrature.
Any pixel values in the dark reference data that are set to NaN
will have their values reset to zero before being subtracted from the science data, which will effectively skip the dark subtraction operation for those pixels.
Subarrays
The dark current is dependent on the detector read mode, therefore subarrays are corrected using the specified read mode.
Arguments
- input
str
|LigerIRISDataModel
The input science data to remove the dark from.
- dark
str
|DarkModel
The name of the dark reference file or a dark model instance. If not provided, the dark is retrieved from CRDS.
Reference Files
dark : Dark current reference file.