Film-Tech Forum ARCHIVE: Dual projector 3D goes out of sync

This is topic Dual projector 3D goes out of sync in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Stephan Shelley (Member # 8587) on 10-10-2015, 11:29 PM:

Here is one to scratch ones head. Two projector passive system. One projector left eye the other is right. Part way through The Martian one projector is out of sync with the other.

Posted by Marco Giustini (Member # 4544) on 10-11-2015, 05:09 AM:

it would help to know what projectors and what media blocks you're using.

I assume it's a media block and not an HDSDI based system. I have no experience with that setup, my only recommendation would be to make sure the software is up to date and then to contact the manufacturer.

Posted by Sam D. Chavez (Member # 1841) on 10-11-2015, 09:56 AM:

I'll let Stephan answer in detail but it is HD SDSI and I'm sure up to date.

Posted by Marco Giustini (Member # 4544) on 10-11-2015, 11:25 AM:

Then it's a single eye system where each projector does its own eye? In that case the delay could be on either HDSDI A or B.

What kind of delay are we talking about? Frames? Seconds?

Posted by Stephan Shelley (Member # 8587) on 10-11-2015, 03:49 PM:

It is HDSDI on Christie 2220 projectors and Dolby DSS/DSP 100. System has been up and running for over 5 years. Server is running system 4.7.3 projectors 4.2. First time in 5 years that this has happended. Hard to say how out of sync but enough frams that you could tell. On cuts you could see one image lag behind the other. Motion in the frame you could see separation change. With glasses on, the elements moving changed 3D planes with respect to the others.

This happened in the last 20 minuets of the feature. Stoping the show and resuming did not help. We switched to 2D to finish. Rebooted the server and projectors during intermission and the next show was fine.