Michael Morris, 22, of Red Hill, handed the prosecution the evidence they needed to charge him with committing an act of indecency on the woman in 2012.

He pleaded guilty to the offence in the ACT Supreme Court.

Morris - the son of wealthy property developer Barry Morris, who heads the Morris Property Group - and his friend, Matthew Holloway, 22, of Bonython, were acquitted last month of raping the woman at the personal trainers’ Red Hill home.

The pair successfully argued the sex had been consensual.

The woman accompanied the two men back to Morris' bedroom about 3.25am on March 12, where they played a drinking game and then had sex.

On Thursday, the court heard Morris recorded about one-and-a-half hours of footage, including the sex, on his laptop without the woman's knowledge.

He deleted the video within hours and forensic experts were later unable to retrieve the erased file. There is no evidence the footage was ever viewed.

The existence of the video remained secret until Morris became aware of the rape allegations.

His lawyers, Canberra firm Ben Aulich and Associates, passed the laptop to the authorities in the hope the Australian Federal Police could recover the footage, after their own experts failed.

But the disclosure resulted in the extra charge being laid against Morris.

A victim impact statement, read out in court, said the woman had been crushed when told of the film.

The statement said the victim’s privacy had been invaded when she had been at her most vulnerable.

She continued to feel unsafe, and limited her life so as to avoid a chance encounter with Morris.

Crown prosecutor Mark Fernandez said the offence had a real and substantial effect on the victim.

Mr Fernandez argued the offence displayed a degree of planning and Morris had shown a lack of remorse.

But defence barrister Jack Pappas said the offender's guilty plea and near immediate deletion of the video displayed contrition.

Mr Pappas argued his client should avoid a conviction.

Chief Justice Helen Murrell ordered Morris to sign an 18-month good-behaviour bond, but did not enter a conviction against him.

Chief Justice Murrell said the offence of filming sex unbeknown to participants was becoming more prevalent.

The judge acknowledged the pain and suffering of the victim, saying the film had been of a "most private nature" and a "serious violation of the victim's privacy".

"The whole thing is extremely unsavoury," Chief Justice Murrell said.

But she also acknowledged Morris had provided the prosecution with the information and means to prosecute him.