0.003 seconds exposure, SBIG ST-8E CCD.
18" f/10.5 Ritchey-Chrétien telescope at prime focus.
Close to the south-eastern limb of the Moon is a large, interesting crater, Petavius. This 107 km diameter crater has complex terraced walls, numerous rills on its floor, and several central peaks. Unfortunately these can be difficult to observe except at favourable libration.
As the Moon approaches full, Petavius appears as a bright ring, however it is difficult to discern as there are bright rayed craters on either side of it and the bright ejecta from these craters almost completely overwhelms Petavius.
When observed shortly after the Sun has risen over the crater or shortly before it sets, Petavius looks quite impressive, with terraced walls, and large central mountain peaks and numerous rills on its floor.
