Marshall invited Spanish-French actress Àstrid Bergès-Frisbey to play Syrena after seeing her in a French magazine article on up-and-coming actresses. Bergès-Frisbey had to take lessons of English, swimming and breath control for the role. The rest of the mermaid portrayers, such as Australian supermodel Gemma Ward, were chosen for having "exotic sense, an otherworldly sensibility, but also under those layers a deadly quality", according to Marshall, and had to take swimming lessons to learn movements such as the dolphin and eggbeater kicks. Principal photography began on June 14, 2010, in Hawaii. Filming was moved to California in August 2010, primarily at the Long Beach shore and a recreation of Whitecap Bay done in the Universal Studios backlot, as the original Hawaiian location on Halona Cove was plagued with strong tides. After a brief shoot in Puerto Rico, with locations in both Palomino Island and the Fort of San Cristóbal in San Juan, production moved to the United Kingdom in September, where principal photography wrapped on November 18 after 106 days of shooting. Locations included Hampton Court Palace in London, Knole House in Kent, and Old Royal Naval College at Greenwich. Interiors were shot at London's Pinewood Studios, and a replica of an 18th-century London street was built on the backlot alongside the soundstages. The producers also considered using New Orleans as a location. In October, security was breached at the UK site when a celebrity impersonator gained access to filming at the Old Royal Naval College by dressing up as Captain Jack. After the joint production of "Dead Man's Chest" and "At World's End" cost over $300 million, Disney decided to give a lower budget to the fourth installment. Many costs had to be cut, including moving primary production to Hawaii and London, where tax credits are more favorable, and having a shorter shooting schedule and fewer scenes featuring special effects compared to "At World's End". The tighter schedule—according to Bruckheimer, "We had a 22-week post, and for a picture like this, with almost 1,200 visual effects shots, it's usually 40 weeks"—meant that Marshall supervised editing of sequences during filming. The British financial statements of the film revealed total expenditures of £240.7 million ($410.6 million) by 2013, with Disney receiving a rebate of $32.1 million from the British government, making "Pirates of the Caribbean: On Stranger Tides" the most expensive film ever made to date.