Heikoff Giant Dome Theater

On my last 2 visits to San Diego (last week and 2 years ago) I saw IMAX films at this domed venue. Both times the films (Journey to the South Pacific and Mysteries of the Unseen World – last week) seemed under lit and less than sharply focused. I was told by the person selling tickets both were being projected in 70mm. I have seen countless conventional 70mm films on large screens that were brilliant and sharp so wondering why the quality is not good at the Space Theater. Also it looked like there was a hole in the screen. I know this theater has been around since the 70’s but it seems like the quality of presentation has become 2nd rate. Anyone know why?