THE ARTICLE IS NOW ACCEPTED (FEBRUARY 21TH 2023) FOR PUBLICATION ON THE ASTRONOMISCHE NACHRICHTEN (AN, Astronomical Notes) and the distortion correction software is now available at this site. soon it will be also available as supplementary on-line material of the Journal. Meanwhile, please, refer to the accepted astro-ph version of the manuscript at this url: https://arxiv.org/abs/2212.03256 We will update the information about the AN Journal article ID Padova, February 22th, 2023 ------------------------------------------------------------------------ Previous ReadMe.txt All the electronic material supporting this article will be made publicly available at this url only once the paper will be accepted. Until then, software, stacked images and catalogues will be available upon reasonable request from the authors. Nov 3rd, 2022