Film-Tech Forum ARCHIVE: Real-D not polarising properly

This is topic Real-D not polarising properly in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Thomas Pitt (Member # 4322) on 08-02-2017, 05:17 PM:

I went to see the new Valerian (City of a thousand planets) movie today in Real-D 3D. The movie started, but there was no 3D - both images were going to both eyes. Many people went out and complained!

This sort of thing has happened before; it usually means that the polariser is not in front of the projector. This time however, the polariser WAS in place, just not doing its job! I could see the staff adjusting the projector; the 3D spacing and phase kept changing. About 8 minutes into the movie they finally got it working again, and very kindly restarted the movie from the beginning so we could see it all in proper 3D.

They didn't have to restart the server or projector - so what do you think caused this issue? Have you ever had similar issues with a Real-D system like this? Also I thought the polariser was supposed to be in place at all times, even for 2D films... moving it away could make it go out of alignment!

Posted by Mark Gulbrandsen (Member # 72) on 08-02-2017, 07:50 PM:

They likely had the wrong macro programed in.

Posted by Monte L Fullmer (Member # 2797) on 08-03-2017, 02:11 AM:

Sometimes, that S-video cable that attaches to the Z-screen can get funky connections.

If the decoder box is displaying normal RealD operation, it's usually that cable. They should unplug and plug back in that cable.

It's best to have that Z-screen out of the way for 2D presentations.

good luck - Monte

Posted by Frank Cox (Member # 6258) on 08-03-2017, 03:09 AM:

My Z-Screen is on a little track that allows me to slide it over out of the way when I'm playing a 2D movie. If it's left in place the picture is dimmer than it can and should be.

Posted by Tom Bert (Member # 5719) on 08-03-2017, 04:57 AM:

Could be wrong (dark) time settings, indeed through wrong macro

Posted by Dave Macaulay (Member # 813) on 08-03-2017, 11:00 AM:

It's not likely a dark time or other 3D file error, that doesn't change and it's very doubtful that anyone at a theatre could adjust it.
If it's a Z-Screen the cable connection is the likely problem. The connectors don't latch in and often get pulled out a bit when moving the screen.
An XL doesn't have that problem as the D connector does screw down.
The wrong macro would definitely lose sync, on an IMB system it would look OK (but no 3D) but on a system with SDI input the colour would be totally wrecked, green or purple (don't recall which way is which - 2D in 3D or 3D in 2D).