 Osbiston was born in Crows Nest, New South Wales, to Charles Alan and Emily Florence "Bae" Osbiston, née Brigstocke of Brockley Farm, Mount Druitt, New South Wales.Osbiston attended "Shore School" and for much of his early life lived in Chatswood, Sydney.Prior to joining the British Ministry of Information, Osbiston worked for Cinesound in Sydney.