Indigenous services librarian Ronald Briggs is used to categorising images, attaching labels like "children at swimming pool".

But it was a shock for the State Library of NSW employee to discover a never-published portrait of his father as a boy of 14 in Moree. His father, Ronald McGrady, was among those "full-blooded and half-caste Aboriginal natives of Australia" banned from the Moree Baths by a council resolution in June 1955.

The photo of Mr Briggs' father, wearing bathers and with a towel over his shoulder, was probably taken when Charles Perkins, the Aboriginal leader of the Freedom Riders, took a group of Aboriginal children into the pool in mid February, 1965, to protest against segregation.

The portrait is labelled, "Ronald McGrady (right) and friend, Moree Pool/ February 1965/ The Tribune."

Now the State Library is asking the public to help identify other people in a group of 101 previously unpublished images of the Freedom Ride. They were taken by a journalist from The Tribune newspaper, Noel Hazzard, who followed the students' bus trip to north-west NSW to protest against Aboriginal living conditions.

The images are posted on Flickr, and will be on display at the State Library from September 5.

Looking at the newly digitised images, Mr Briggs spotted his dad. "I found this one, and I thought, "oh, that's dad". I freaked out," he said. "I just couldn't believe it," he said of his father, who was raised on the mission in Moree and died in 1984, aged 34.

"I remember him being a grumpy old hairy guy, telling me what to do. But seeing (dad) as a baby-faced boy is amazing," he said. The family has only a handful of images of the young Ronald McGrady; cameras were too expensive in those days for his family.

The photos document the Aboriginal people in the missions, reserves and camps in Moree and Walgett. They include images of the Freedom Riders — students from Sydney University — including Mr Perkins, one of the the university's first Aboriginal students, and Ann Curthoys, who wrote a book to document and expose Aboriginal living conditions.

Ms Curthoys wrote that it was the Moree leg of the trip that most people now remember. "And it was in Moree that so many people now say the Freedom Ride changed race relations forever," she wrote in her book.

At the pool, Mr Perkins asked for a ticket for himself "and these 10 Aboriginal kids behind me".

But the manager replied, "Sorry, darkies not allowed in."

Mr Perkins entered anyway. A few days later, when the Freedom Riders heard that the council had reneged on a promise to lift the ban, they returned, collecting children from the mission to take into the pool.

In May 1965, Moree Mayor Lloyd — the same man who is seen in the photos escorting one of the protesters away from the pool — moved a motion to rescind the ban. It was passed.

The images were contained in the archives of the Communist Party's newspaper, The Tribune, which were donated to the State Library in 1992. The Library is slowly digitising the 60,000 negatives from the newspaper's photo archives which covers protests in the 1960s, 70s and 80s including the Vietnam War, women's rights, gay rights and anti-apartheid protests.