Paramount subsequently brought in Petru Popescu to alter the screenplay and make it "more sinister and menacing." Though the final filmed version of the script contained significant contributions from Popescu, he remained uncredited. The script for "Part III" called for Jason to wear a mask to cover his face, having worn a bag over his head in "Part 2"; this mask would become a trademark for the character, and one instantly recognizable in popular culture in the years to come. Screenwriter Popescu said casting was based on looks rather than talent, and recalled that his vision of the characters was at significant odds with the cast chosen by director Steve Miner. Dana Kimmel was cast in the lead role of Chris Higgins after Miner had become aware of her involvement in "Sweet Sixteen", another slasher film she had appeared in with Bo Hopkins and Susan Strasberg. Tracie Savage, who had previously worked as a child actor, was offered the role through her agent. Larry Zerner was discovered by casting directors while walking along a street, and was offered the role of Shelly. For the role of Jason Voorhees, Miner cast British stuntman Richard Brooker. Georgetown Productions, who had produced the previous two installments in the "Friday the 13th" series, was initially involved in the pre-production of "Part III", agreeing with distributor Paramount Pictures to shoot the film with 3-D cameras, making it the first Paramount film produced in 3-D since "Jivaro" in 1954. Paramount leased two 3-Depix cameras from the photography company Marks Polarized Corporation to shoot the film. Simultaneously, Paramount executive Al Lo Presti was researching current 3-D camera technology with the intention of developing a 3-D lens to be owned and used exclusively by Paramount. According to a September 1982 issue of "Forbes" magazine, Sirius II Corp. owner Gale Weaver visited the set of "Friday the 13th Part III", reportedly over producer Frank Mancuso, Jr.'s worries that faulty projection lenses at cinemas would prevent the film from having a wide theatrical release. Over a two-week period, Weaver developed a prototype lens that would be adaptable to "almost all theater projectors"; Paramount subsequently awarded Sirius II Corp. $1 million to manufacture the lenses, which would be used in projection—to the exclusion of Marks projection lenses. Marks Polarized Corporation subsequently filed a $25 million lawsuit against Paramount, alleging that the studio was "monopolizing the marketing of 3-D exhibition materials, as well as providing deductions to theaters choosing to lease projection lenses directly from Paramount."