Hubble Ultra Deep Field in 4K

The Hubble Ultra Deep Field (HUDF) is a composite image - it uses data collected by the Hubble Space Telescope. Between 24 September 2003 and 16 January 2004, it observed a small area of sky in the Fornax constellation, completing 400 orbits of Earth in the process. The Advanced Camera for Surveys, a wide-field camera, took 800 exposures - the total exposure time was ~ 1 million seconds or 11.3 days on aggregate. Is it a true-colour image? It is to an extent - the area of sky was observed in visible to