Didn't want to get too deep into VV and its variants but yes, ILM resurrected VV for effects. 70mm was also used for effects back in the day to reduce graineness when added into 35mm (Close Encounters). Suoer 35 can use the full negative but only the inented ratio is whats shot for. Opening it up can lead to microphone booms in the frame or the endless bicyle chain in Pee Wee's Great Adventure
. A lot of S35 directors have in in their contracts they ratio can only be altered under their supervision. Others like Ron Howard prefer to "hard matte" (blocking the unuse portions) to prevent studios from screwing around with it
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