This code is inspired on Zackay & Ofek 2017 papers How to coadd images?

It can perform the statistical proper coadd of several images using a spatially variant PSF estimation.

Images need to be aligned and registered.

Documentation at https://properimage.readthedocs.io .

Zackay, B., & Ofek, E. O. (2017). How to COAAD Images. I. Optimal Source Detection and Photometry of Point Sources Using Ensembles of Images. The Astrophysical Journal, 836(2), 187. http://arxiv.org/abs/1512.06872

Zackay, B., & Ofek, E. O. (2017). How to COAAD Images. II. A Coaddition Image that is Optimal for Any Purpose in the Background-dominated Noise Limit. The Astrophysical Journal, 836(2), 188. http://arxiv.org/abs/1512.06879