A Canberra man who took pictures of women's crotches without their knowledge has won an appeal against his conviction, after a judge found he did not breach the women's privacy.

Jason Stroop, 44, was found guilty of taking indecent images of the women in March.

In one instance Stroop took pictures of a woman in activewear as she squatted down. The other image was of a 17-year-old girl who was squatting while wearing shorts.

Both photographs were taken from a low angle without the victims' consent and focused on their groin areas.

While Stroop was originally found guilty in the ACT Magistrates Court, Justice David Mossop overturned the decision.

Justice Mossop did not challenge the finding that the images had been indecent, but questioned whether they had breached the victims' privacy.

"In each case the victim was dressed and hence only exposing to the view of strangers those parts of the body which they wished to," he said.

"I do not consider that it is enough that the combination of indecency and lack of consent amounts to an invasion of privacy."

The judgment, handed down yesterday, said while the victims would not have expected to be photographed, Stroop's pictures did not amount to "upskirting or downblousing", where body parts intended to be covered with clothes were photographed.

Justice Mossop allowed the appeal and dismissed Stroop's conviction.