The angular differential imaging (ADI) improves contrast in the astronomical imaging.An example is direct imaging of exoplanet in camera fed by Extreme Adaptive Optics. The subtraction of the main dazzling object to observe the faint companion was improved using Principal Component Analysis (PCA). It factorizes the positive astronomical frames into positive and negative components. On the contrary, the Nonnegative Matrix Factorization (NMF) uses only positive components, mimicking the actual composition of the long exposure images.

This presentation is part of Minisymposium “MS9 - Innovative models and algorithms for astronomical imaging (2 parts)”
organized by: Silvia Tozza (INdAM/Dept. Mathematics, University of Rome “La Sapienza”) , Marco Castellano (INAF Osservatorio Astronomico di Roma) , Maurizio Falcone (Dipartimento di Matematica, Università di Roma "La Sapienza") , Adriano Fontana (INAF Osservatorio Astronomico di Roma) .

Authors:

Carmelo Arcidiacono (INAF Osservatorio Astronomico di Bologna)

Keywords:

image enhancement, image reconstruction, numerical linear algebra