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.