Circa 1998/1999, Helen took her camera with her when she left the present day to travel through the Anomalies. (Episode 1.1, Series 1) Helen probably had it when she was captured by the Home Office. (Episode 1.3, 1.4)
After discovering futuristic predators in the Permian period, Helen travelled to 2006/2007 and helped convince the Home Office to send a mission to the Permian so she could find the future Anomaly. Once there and after Nick, Captain Ryan and some other soldiers had set up a campsite, she took some photos of Scutosaurus with her camera. Helen then called Nick up to the ridge she was sitting on and asked him to take some photos of her. He took several photos then realised that the photos were the same as the camera that his younger self had discovered and Nick realised that, thanks to a time loop, they had created their own past. Suddenly a Predator and a Gorgonopsid fought, destroyed the campsite and killed all the soldiers. Both Cutters buried the men, and Nick also secretly buried Helen's camera with Ryan's body so his younger self could find it.
Many years later, younger versions of Nick and Captain Ryan travelled to the Permian and discovered the remains of the camp. Ryan found the graves and the camera then gave it to Nick who recognised it as Helen's (who he had not seen for eight years from his point). They returned to the present with it and the Home Office developed the camera's film then Nick, James Lester and Claudia Brown viewed the photos of Helen in the Permian. Either Nick or the Home Office kept the camera afterwards.