"This has been of great assistance to the investigation team," police said in a statement.
The armed robber was described as being a white man in his early 30s, about 5'10", unshaven, with light coloured hair.
He was wearing a dark coloured beanie and a dark long sleeved top. He would have been carrying another hat in his hands as he made off from the service station.
A scene examination was completed this morning and CCTV footage was being reviewed, police said.
Anyone who was travelling in the area of Main St/Victoria Ave around 9.15pm to 9.30pm who saw a man walking in the area fitting the above description is asked to contact Detective Sergeant David Thompson at Palmerston North Police Station, on 06 351 3600, or anonymously contact Crimestoppers on 0800 555 111.
NZH pd