She could use a dozen pieces of tape, the note would still fall off
I really enjoyed this film. I'm a huge fan of Time Travel/Time Loop films. My 3 all time favourites are Triangle, Time Crimes and Primer. The following is how I view this film and I am certain there is nothing on screen that contradicts my theory. By the same token, it can be viewed many different ways, and again be supported by what is shown on screen. But anyway, this is my theory and I'm open to anyone challenging it.
My theory is that this film is very unique among Time Travel/Loop films. Most films in this genre involve multiple timelines where the characters can manipulate the future or the past, sometimes even coming into contact with other versions of themselves. The difficulty with creating airtight story lines is the ever present time paradoxe. Very few films can avoid these plot holes. Example: Back to the Future part 11: After old Biff gives his younger 1955 self the Sports Almanac, he should not be able to get back to his present time and leave the car for Marty and Doc to find. The minute he hands over the Almanac, he has created an alternate timeline and can only move within that timeline. Finding these plot holes is great fun and part of what makes these films so fascinating. The above 3 films I mentioned are unique in the genre in that they hold up very well with no significant plot holes at all.
But coming back to Time Lapse. I do not believe that Time Lapse is a Time Travel/Loop film at all. I believe that in Time Lapse there is only ever 1 timeline, and that it cannot be manipulated. Everything the characters see in the future has to happen that way and cannot be tampered with. Last night while discussing the film, one of my friends said that the characters went out of their way to set up the situations in the future polaroids. I disagree, I think that no matter what they did, that situation would always arise. So when Finn packs his bags and says he is leaving, there is no danger of him changing the future and creating a paradox. He cannot leave, because the future has already said that he will be on the couch.
Warning: Spoilers ahead!!
Hence my Subject heading: She could have used a dozen pieces of tape, the note would still have fallen off. Callie believes that she has been manipulating events and can undo what has just happened, by simply putting up the note saying 'Don't get caught at Window'. She is however wrong. She has only been doing what has already been written in the future. In this film the characters cannot change anything once they've seen the next days polaroid.And if they decided to nly look at the polaroid after the moment in question, the polaroid would simply show what they had just been doing.
So no matter how securely Callie puts up that note, it will always fall of, because the future has already shown the window without it.