Parkes was second to build on his 'guest' points tally, comfortably up on Easton, who was a lonely third position to further close the gap on provisional runner-up James Ellison in the overall standings.
Off the podium, things proved somewhat closer, with Tommy Hill eventually prevailing to make it four different manufacturers inside the top four positions.
The Suzuki rider ended the opening lap in fifth position, but rallied hard to catch and overtake a fading Karl Harris with four laps remaining, before attempting to launch a late assault on Easton for third. Nonetheless, fourth marks his best race result since returning to the series.
Ellison crossed the line in fifth position on the second Airwaves Yamaha after picking his way through the order following a poor start that left him down in ninth initially.
His exchange with Steve Brogan was particularly entertaining, the Superstock rider doing a mighty job of keeping the two-time BSB race winner behind him for several laps. Ellison would ultimately find a way through when Brogan's attempt to pass Chris Walker ahead forced him to sit-up and lose a place to both the Yamaha rider and HM Plant Honda team-mate Karl Muggeridge.
Having been caught and passed by Ellison in the latter stages, Harris followed in sixth position, with Muggeridge and Brogan crossing the line in tandem in seventh and eighth.
Graeme Gowland upheld Motorpoint/Henderson honours in ninth after Walker, who was heading for the same position, retired two laps from the conclusion of the race with a mechanical problem.
Having crashed out of the opening race, Sheridan Morais rounded out the top ten on the second World Superbike Kawasaki, the South African making steady progress after a dismal start saw him drop from third to 15th by the end of the opening lap.
Julien Da Costa kept the points ticking over in 11th, ahead of Ian Lowry, John Laverty, Cup winner Gary Mason and Atsushi Watanabe.
In the overall standings, Camier is now an unprecedented 104.5 points ahead of Ellison, who remains a relatively comfortable second, 40 points up on Easton.