Les Eade was kind enough to take me up for the early morning sniffer flight in his Rans S-6ES ZK-LVE. These two views show the Rangitata Island airfield. Above we are at the start of the a longish left hand downwind leg for vector 12. The white building mid picture is the "Moth Manor" with the mown strip between the two tree rows. The Rangitata River (North Branch) is towards the topright. SH1 enters the right hand side about one third of the way down the pic and continues across at about that level.
Photo below shows us turning onto final for 12 with the start of the mown strip behind the tall tree left of centre.