Film-Tech Forum ARCHIVE: Real-D 3d problems solve themselves?

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Posted by Tom Inglis (Member # 5181) on 07-01-2009, 04:27 AM:

Two nights ago, I was proofing our 3d copy of Ice Age 3, and the entire film suffered from double imaging problems (and yes, i was wearing my glasses). I had my colleague check it out that night, and two of my friends saw the same problem.

I dashed off a note and an e-mail to alert the proper people, and left it with the guys the next day.

I get a phone call the next day, our PM and another colleague both checked it the in the morning and it was crystal clear.

any thoughts on what could have caused this?

The only thing that changed was our porthole glass, but we ran Coraline on the old normal glass, and it was fine... so i don't get how it could make such a difference...

Posted by Julio Roberto (Member # 4976) on 07-01-2009, 06:24 AM:

Very theoretically, and although probably not your case, anything depolarizing about the porthole (i.e. some coatings, plastics, cellophane films, and stuff like that) definitely could totally screw the Real-D system by depolarizing the light before reaching the (silver) screen, producing the symptoms you describe.

Needless to say porthole glass usually does not have anything "weird" like that and, at most, may have an anti-reflection coating. So, again, this is only in theory.

Sounds like perhaps the real-D Z-screen was either not functioning at all or totally out-of-sync with the image. This may have been caused by many factors, from it not receiving power to loose contacts in the cabling from the projector interface to electronic defects.

If everything was verified to be setup correctly, the unit "turned on" etc and the problem was there only to dissapear by itself the next day ... I'm afraid it may re-appear at any time.

The porthole COULD be a cause that would explain 100% your symptons, but leave you scratching your head about Coraline. It's just as well a very unlikely one, though.

I don't know. Theoretically, even some (unusual, oily, anti-dust coating) cleaning product applied to the glass could act as a de-polarizer film.

So, again, while in theory it's totally plauseable, I don't see how anybody would make anything so radical to a porthole glass to, in practice, explain your case.

Posted by Darryl Spicer (Member # 711) on 07-01-2009, 10:49 AM:

Not sure what projector system you are using but I had something similar with double imaging or 3-D not working proerly...the fix was to switch to the opposite 3-D format and then back to the format that you are useing on the touch pad. This was on a Christie cp2000s. Cleared the problem up.

Posted by Todd McCracken (Member # 4718) on 07-01-2009, 11:47 AM:

More than likely it was your projector settings (the dual image was possibly inverted)

Posted by Mark Gulbrandsen (Member # 72) on 07-01-2009, 10:05 PM:

I tend to agree more with Julio not only because I've seen this actually happen because of the glass but because he figured out that I had my Blu-ray player setup wrong... saved me alot of grief trying to take a perfectly good disk back to
the store [thumbsup]

Posted by Tom Inglis (Member # 5181) on 07-02-2009, 07:35 PM:

we double checked the settings while it was running, and they were all fine.

the current theory-du-jour is that for this particular show, we swung the zscreen into place AFTER the programme had started. i thought that it just acted as a filter sort of thing... am i wrong? could this have caused our problems?