Film-Tech Forum ARCHIVE: Screen bulging out?

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Posted by Thomas Pitt (Member # 4322) on 05-15-2010, 01:37 AM:

I just went to see the remake of Nightmare on Elm Street, and noticed a patch of distortion on the screen; assumed it was a dent. After the movie, I took a closer look at the screen. It wasn't a dent, but a BULGE. The screen was actually bulging out (towards the seats) at that point!

I can understand the screen denting or tearing if people throw stuff at it, but what would cause the screen to bulge outwards like that?

Posted by Michael Voiland (Member # 5386) on 05-15-2010, 01:48 AM:

Did you take a peek behind the screen. Your speaker might have started to tip forward and well come off the stage behind the screen.

Posted by Cameron Glendinning (Member # 3516) on 05-15-2010, 02:01 AM:

I have seen speakers do this. I have also worked in a big IMAX that has a "belly" simply due to its huge size!

Posted by Christopher Crouch (Member # 3784) on 05-15-2010, 06:08 AM:

I would guess either a speaker or some item that they are storing fell forward into the screen. I've seen too many theatres that utilize the back screen area like a storeroom (ladders, left over construction materials, broken equipment, etc.).

Posted by Ken McFall (Member # 845) on 05-15-2010, 06:11 AM:

Is it a curved screen frame?

If so it could be over tensioned and pulling the horizontal out of it's curve...

Posted by Chris Slycord (Member # 4239) on 05-15-2010, 11:26 AM:

This can especially happen bad on the dreaded Torus screens if the vacuum behind the screen stops working. You'll get pretty big sags.

Thankfully, I haven't dealt with those in quite a while.