# \#difference-imaging

**URL:** https://www.rubin.community/tag/difference-imaging/255.md

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## [Questions about the image being subtracted in the AP pipeline](https://www.rubin.community/t/questions-about-the-image-being-subtracted-in-the-ap-pipeline/8820)

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**Author:** [@sfu](https://www.rubin.community/u/sfu)\
**Replies:** 9\
**Last updated:** [July 18, 2024, 8:54pm UTC](https://www.rubin.community/t/questions-about-the-image-being-subtracted-in-the-ap-pipeline/8820 "2024-07-18T20:54:16Z")

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Hi all, I have two questions regarding the image being subtracted in the AP pipeline. I didn’t find how to use the LSST pipeline to do image subtraction between two coadded images. LSST takes a pair of 15s exposures …

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## [What causes difraction patterns in difference images?](https://www.rubin.community/t/what-causes-difraction-patterns-in-difference-images/6829)

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**Author:** [@stevenstetzler](https://www.rubin.community/u/stevenstetzler)\
**Replies:** 1\
**Last updated:** [July 1, 2022, 3:23pm UTC](https://www.rubin.community/t/what-causes-difraction-patterns-in-difference-images/6829 "2022-07-01T15:23:53Z")

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Hi, I am just wondering what causes patterns like this in a difference image: Does it have to do with a mismatch between the template and calexp PSF during PSF matching? Was either the template or calexp PSF model m…

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## [Difference Image Driver](https://www.rubin.community/t/difference-image-driver/2622)

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**Author:** [@jrmullaney](https://www.rubin.community/u/jrmullaney)\
**Replies:** 3\
**Last updated:** [January 26, 2018, 3:20pm UTC](https://www.rubin.community/t/difference-image-driver/2622 "2018-01-26T15:20:01Z")

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Hi all, As mentioned in previous posts, we’re writing our own obs\_ package for a wide-field survey telescope. It’s working really nicely through to difference imaging (we’ve not experimented much with forced photometry)…

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## [How will the difference imaging pipeline respond to marginally resolved sources?](https://www.rubin.community/t/how-will-the-difference-imaging-pipeline-respond-to-marginally-resolved-sources/2306)

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**Author:** [@dannygoldstein](https://www.rubin.community/u/dannygoldstein)\
**Replies:** 2\
**Last updated:** [October 17, 2017, 3:46pm UTC](https://www.rubin.community/t/how-will-the-difference-imaging-pipeline-respond-to-marginally-resolved-sources/2306 "2017-10-17T15:46:12Z")

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I am trying to understand how the LSST pipeline will handle blended point sources (i.e., strongly lensed supernovae with marginally resolved multiple images). To make things a bit more concrete, I’ve attached an example…