Forensics expert Roger Dixon is continuing to testify at Oscar Pistorius’ murder trial in South Africa’s capital, Pretoria.
He took the stand after the Olympic sprinter’s seven days of testimony came to an end with him reading a Valentine’s card from his girlfriend.
The athlete denies intentionally killing his Reeva Steenkamp in early hours of 14 February 2013.
He says he shot her in the toilet, mistaking her for an intruder.
The prosecution says the 29-year-old model and law graduate was deliberately killed after the couple had an argument.
The double amputee Paralympic athlete faces 25 years to life in prison if convicted of premeditated murder.
On Tuesday, Mr Dixon, who is a defence witness, told the court his tests showed that with the light out, Mr Pistorius’ bedroom would have been almost completely dark on the evening of the shooting, despite a couple of LED lights.
This supports Mr Pistorius’ evidence that he did not see whether Ms Steenkamp was still in bed when he got up
The court also heard sound recordings Mr Dixon had made – of a cricket bat striking a door similar to that in Mr Pistorius’ toilet, and of gunshots fired through same door.
Mr Dixon seemed to struggle to tell the sounds apart, which the BBC’s Pumza Fihlani in Pretoria says the defence will use to cast doubt on what neighbours say they heard that night.
Prosecution witnesses have testified to hearing a woman scream followed by gun shots, but the defence disputes their testimony, saying the only scream came from Mr Pistorius – after he had fired.
At the start of proceedings on Wednesday, the judge agreed to an application to postpone the case after Thursday’s hearings until 5 May.
If Mr Pistorius is acquitted of murder, the court must consider an alternative charge of culpable homicide, for which he could receive about 15 years in prison.
He also faces charges of illegally firing a gun in public and of illegally possessing ammunition, both of which he denies.
There are no juries at trials in South Africa, and his fate will be decided by the judge, assisted by two assessors.
Mr Pistorius is known as the “Blade Runner” because of the carbon-fibre prosthetics he uses on the track.
Mr Pistorius said in his statement at the start of the trial that he woke in the early hours and walked on his stumps to the balcony, pulled in two fans, closed the sliding door and drew curtains. He said that shortly before he had spoken to Reeva, who was in bed beside him.
He said he rejected prosecution claims that a witness heard arguing coming from the house before the shooting.
2. Bathroom window
Mr Pistorius said he heard the bathroom window sliding open and believed that an intruder, or intruders, had entered the bathroom through a window which was not fitted with burglar bars.
“Unbeknown to me, Reeva must have gone to the toilet in the bathroom at the time I brought in the fans,” he said.
Mr Pistorius said he approached the bathroom armed with his firearm, to defend himself and his girlfriend, believing Ms Steenkamp was still in bed.
Both sides agree four bullets were fired. Ms Steenkamp was hit three times.
Mr Pistorius said he fired his weapon after hearing a noise in the toilet which he thought was the intruder coming out of the toilet to attack him and Ms Steenkamp.
He said he was in a fearful state, knowing he was on his stumps and unable to run away or properly defend himself.
Mr Pistorius said he rejected claims that he was on his prostheses when he shot at the door.
A witness told the trial she woke to hear a woman screaming and a man shouting for help. She said that after the screams she heard four shots.
Mr Pistorius said he went back to the bedroom after shooting at the toilet door, still shouting for Reeva. Lifting himself up onto the bed, he felt over to the right hand side of it and noticed Ms Steenkamp was not there.
Mr Pistorius said this was when he realised she could have been in the toilet.
5. Toilet door
Mr Pistorius said he went back to the bathroom but the toilet was locked, so he returned to the bedroom, pulled on his prosthetic legs, turned on the lights before bashing in the toilet door with a cricket bat.
Forensics expert Johannes Vermeulen told the court that the height of the marks on the door caused by the cricket bat suggest Mr Pistorius was on his stumps at the time.
6. Emergency calls
Mr Pistorius’s defence team say he then called security at the gated housing complex and a private paramedic service before carrying Ms Steenkamp downstairs.
A security guard claimed it was the other way round, and he had called Mr Pistorius first after reports of gunfire. However, phone records shown to the court revealed Mr Pistorius called the estate manager at 3:19am, a minute later he called the ambulance service and at 3:21am he called estate security.
A minute later he received an incoming call – estate security calling him back.
According to police phone expert Francois Moller, Mr Pistorius called his friend Justin Divaris a short time later and just after 4:00am he called his brother Carl.