JWST NIRCam subpixel dithers are small pointing offsets between exposures that mitigate an undersampled PSF and bad detector pixels.
Overview of NIRCam subpixel dithers
NIRCam subpixel dithers are small pointing offsets performed between exposures in imaging, coronagraphy, and wide field slitless spectroscopy observations. They include subpixel offsets designed to mitigate undersampled PSFs. The available subpixel dither patterns serve different purposes for different observing modes:
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