Changes in the position of objects, visible in photos of the scene of Reeva Steenkamp's death, were questioned in the High Court in Pretoria on Tuesday.

Barry Roux, for murder-accused paralympian Oscar Pistorius, began his cross-examination of police photographer Warrant Officer Barend van Staden.

He compared two photos of a cricket bat lying on the blood-bespattered floor of Pistorius's bathroom, near a bloodied grey towel.

Pistorius used the bat to bash open the door of his toilet after he shot and killed his girlfriend Steenkamp through it, apparently believing she was an intruder.

Referring to the make of the bat visible on its back side in one photo, Roux asked Van Staden: "Do you see where the line of the tile bisects the word Lazer?"

It ran through the "e", Van Staden said.

Roux called up a second photo, displayed on screens around the court, showing the bat from a different angle.

The joint between the tiles now ran through the letter "r", Van Staden said to Roux's question.

"It seems there was movement of the bat," Roux said.

Van Staden replied: "It seems so."

Proceedings began an hour-and-a-half late as Van Staden had to fetch the master copies of the crime scene photos from his office.

Van Staden is attached to the photography section of the Local Criminal Record Centre. He had been with the centre for 12 years, and in the police for 21.

In addition to the charge of murder, Pistorius is charged with contravening the Firearms Control Act.

He allegedly fired a shot from a Glock pistol under a table at a Johannesburg restaurant in January 2013.

On September 30, 2012 he allegedly shot through the open sunroof of a car with his 9mm pistol while driving with friends in Modderfontein.

Pistorius has denied guilt on all the charges.