SATELLITE television station STAR TV's sister company, Media Assets, is set to make a $50 million investment in the Hongkong TV film industry. Media Assets, a programme acquisition company, will finance the shooting of 25 productions in Hongkong and China. Twelve of the productions are to be filmed in the territory and will be premiered on STAR TV's planned ''pay per view'' channels when the station begins transmitting six subscription services at the end of this year. The remainder will be shot in China in Mandarin with budgets of between $1.8 million and $2.5 million. But it is unlikely Hongkong's best-known performers will appear. ''The fact is you are not going to get the big stars like Ronnie Yip and Andy Lau appearing in these because the budgets are too small. They will sign second division actors and actresses,'' one independent sector director said. The 12 Cantonese films will be shot on Super 16 millimetre film and not on video - the medium normally used for TV films - because they will also be released for showing in movie theatres. This will further reduce the available budget because technicians and actors have to be paid more for working in the Super 16 format than for video. Another independent director, Cha Cheun-yee, of Concept Link Productions, said: ''Productions using Super 16 are much more complicated. There have to be more people in the crew and they have to be paid more. ''But if these are successful I think they will be able to attract bigger budgets and therefore bigger stars in the future.'' Both directors said they had been approached informally by Media Assets about the projects, although no deals had been signed. They believed that shooting would not start until later this year. Media Assets is trying to build up a library of programming to feed into STAR TV. As more satellite channels go on air over Asia programmers are finding there is a shortage of programming to feed them. ''We are looking to build up a significant media portfolio, not only to sell at arms length to STAR TV, but also for distribution around the world,'' said one Media Assets executive, who asked not to be named. ''But bargains when you are looking for ownership of copyright are hard to come by.'' Media Assets has looked into buying software libraries all over the world, ''but it is surprising how few of them are suitable for Asia'', the executive said. ''Buying Asian libraries is also a problem since the rights of most of them have already been leased for up to 10 years.''