Crown raises night vision issue

What is the blackest time of night and how a person's sense of colour can become warped after sunset were questions tackled in the High Court at Wellington yesterday.

A crown witness in the Scott Watson murder trial, astronomer Brian Carter, told the court that the sun set at Furneaux Lodge at 8.59 pm on December 31, 1997.

Between 11.06 pm and 3.47 am next day was the darkest time of the night, he said. After 3.47 am light began to return.

Ben Smart, aged 21, and Olivia Hope, aged 17, were last seen leaving a water taxi and boarding a yacht with a stranger in Endeavour Inlet between 4 am and 4.30 am on New Year's day.

Producing a colour chart of black, white and seven primary colours, Mr Carter told the court all colours look like different shades of grey between 60 and 90 minutes after sunset.

The moon that night was a "very thin crescent," so would have no effect on light or colour.

Defence counsel Mike Antunovic asked him: "You are presuming there are no other sources of light."

"Yes," he replied.

A point of contention during the three-month murder trial is expected to be the varying descriptions of the boat the Blenheim friends were last seen boarding, and who they were with.

The court heard earlier in the day that the first bulletin given to marine radio after the pair disappeared asked people to look for a white and blue ketch.

Inspector Stephen Caldwell, who headed the investigation in its early stages, said the first information was given to Blenheim Marine radio on January 2 and 3.

On January 5 and 6, faxes were sent to the radio station and the media describing the suspect boat.

The boat's description was put together after an interview with the water taxi driver, Guy Wallace, who dropped the pair off.

Under cross-examination from defence counsel Bruce Davidson, he read out the press releases. The first described the suspect boat as "similar to a ketch," with a white hull, blue stripe and round portholes.

The next press release, on January 6, described the boat as having traditional styling, 1960s, wooden, white with a blue line above the water line, with a flexi side rail and lots of rope.

Watson's boat, Blade, which was pulled from the water and impounded by police on January 12, was a one-masted sloop which had been red on the night in question.

The Crown also called several witnesses to describe to the court the extensive land, sea and air searches, and the early parts of the investigation.

Gerald Hope, Olivia's father, told the court how his family, the Smarts, and up to 500 volunteers searched Queen Charlotte Sound from Grove Arm to the open sea.

The search extended for 10 weeks from January 2 - the day after his daughter was due to come home.

Supported by more than 120 boats, the Smarts and Hopes knocked on doors of baches, and stopped boaties at marinas and at sea.

Their searching covered several hundred kilometres of coastline, as well as every inlet, waterway, cove and island in the sounds.

Mr Hope told the court how searchers were dropped on to remote coastline even in rough seas, unless a "sheer rock face" forbade it.

"We set up a network. We would knock on doors and ask people to keep an eye on their bay. People would go out fishing and keep an eye out."

Volunteers were given photos of the children, descriptions of the items they had taken on holiday, and told to mark a map if anything of significance was found.

"If there were remains of a body found, they were told to leave it untouched unless it was in the water," said Mr Hope.

"And did you find anything of significance?" asked crown counsel Paul Davison, QC.

"There was nothing, absolutely nothing," said Mr Hope, looking to the back of the court to where Scott Watson was sitting in a dark suit, flanked by prison guards.

The court also heard of exhaustive police searches of Queen Charlotte Sound, which also failed to find any items connected to the missing pair.

Today the court is expected to hear from boaties and holiday-makers who were at Furneaux Lodge and in Endeavour Inlet over New Year.