Film-Tech Forum ARCHIVE: Christie 3D wobbly image

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Posted by Adrian Hauser (Member # 4723) on 12-07-2012, 05:30 PM:

Hi,
We have a christie Cp2210 3D projector.
I have noticed when viewing a static/paused image in 3D without glasses, that the on screen 3D Left and Right images slightly wobble against each other.
I have no idea what is causing this.
I thought it may be because the aircon was moving the screen slightly which may show a similar effect but this is not the case.

EDIT: I have noted this when activating EITHER Dolby3D or XPanD which are available on the projector.

Has anyone noticed this?
thanks
Adrian

Posted by Randy Stankey (Member # 64) on 12-07-2012, 06:55 PM:

I don't know the cause but just curious.

How fast does the image wobble?
Could it be because the projector is rapidly displaying the left and right fields in succession?

In other words, could this be a normal consequence of pausing an image, much the same way that pausing a VCR can show a jittery image when the interlaced odd/even fields are diaplayed?

Even though the cinema projector is a progressive display, not an interlaced one, the left and right fields could act the same way.

As I said, just a guess...

Posted by Sam D. Chavez (Member # 1841) on 12-07-2012, 08:04 PM:

I am confused here. The 2210 does not support Dolby 3D last time I checked so some information is wrong here.

Posted by Andrew Thomas (Member # 7000) on 12-08-2012, 11:02 AM:

The images are mostly the same, but not exactly the same (or you wouldn't get a 3D effect). I assume when paused the Projector still alternates back and forth between the left and right eye image which makes it look like the screen is wobbling.

Posted by Adrian Hauser (Member # 4723) on 12-08-2012, 03:06 PM:

The wobbling / horizontal pulsing effect is strange indeed.

It has a cycle of about 1 -2 'wavers' per second and has a randomness to it.
It is definately NOT the two images being flashed in succession. If it were the two images on screen would still not horizontally waver against each other on a static frame.
IE at one point in the cycle of the 'wavering effect" the images are closer to each other, and at the other point in the cycle they are further away from each other.
It is a similar effect if we were to adjust the convergence between the eyes thus making the stereo image appear closer to the audience of further away.

A colleague just suggested that they have had a very similar situation on their christie that was caused by a external cooling fan that was oscillating the projector head. Ill look into this.

Adrian

Posted by Danial Simmonds (Member # 4638) on 12-18-2012, 02:26 AM:

If using the latest solaria version you might need to go and edit 3D High Frame Rate under Advanced tab