The projectors in the theater where he got shot seem older than the ones at the institute. Maybe they are a lot louder. Noise would come from the sprockets and that stuff but also the fan to keep the bulb cool. Maybe so loud his nickle trick wouldn't work so he didn't use it. Also think about how ling thise reels are. In Make Me a Perfect Murder they were just over 10 minutes each. That would make them 1,000 feet. In this one they could have used 2,000 foot reels or abour 22 minutes.