AlardLuptonPreconvolveSubtractTask#
AlardLuptonPreconvolveSubtractTask is a modification of AlardLuptonSubtractTask behavior, and it performs image differencing between the template image and a custom kernel cross-correlated science image.
Description#
This task takes the pair of science and template exposures, together with the science image source catalog, and produces difference and matched template exposures as outputs.
The process involves pre-convolving the science image with a predefined kernel (tipically its own PSF) before running the nominal set of steps for image subtraction, that is, selecting sources to obtain a matching convolution kernel, applying this to the template image, and performing the image differencing.
In this case the subtraction produces a score image directly, and it can be used for maximum-likelihood source detection in a straightforward manner. This is done using DetectAndMeasureScoreTask.