Film-Tech Forum ARCHIVE: Real D causing focus uniformity error

This is topic Real D causing focus uniformity error in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Eric Robinson (Member # 2966) on 01-23-2012, 11:21 PM:

I have a theatre whose employee states that the image from our Barco projector is in focus with no devices between the light output of the lens and the screen; however, when the Real D unit is slid into position in front of the lens, the lower half of the image is out of focus.

The Real D unit is left in front of the lens all the time while a 3D movie is assigned there. So, when the pre show comes on, it goes through the Real D unit and it is here that the focus uniformity is problematic.

Does anyone know if there is an adjustment for such a problem?

This is a Barco series 2 projector with a Real D 3D unit that slides back and forth on lateral rails into or out of the lens path.

We got one of those slam-bam installs without any technical training what so ever on the Real D 3D units.

Posted by Monte L Fullmer (Member # 2797) on 01-24-2012, 12:41 AM:

Sounds like nobody did any internal adjustments to align the image to the Real D "XL' unit. Or, somebody got into the adjustment screen and messed with the settings.

Better call them back and do the job right.

How does 2D playback look - pull the XL unit aside when the preshow is going and see how that looks...

Posted by Eric Robinson (Member # 2966) on 01-24-2012, 12:26 PM:

Monte:

quote: Eric Robinson
the image from our Barco projector is in focus with no devices between the light output of the lens and the screen

from above. Thanks for your input. Presumably it looked good after the install, but is now out of whack.

Posted by Carsten Kurz (Member # 5396) on 01-24-2012, 03:58 PM:

Is it the normal ZScreen or the XL?

- Carsten

Posted by Darryl Spicer (Member # 711) on 01-24-2012, 10:09 PM:

How does the focus look with the RealD 3-D glasses on? It is possible to knock out the mirror adjustment if you push the RealD XL unit to hard against the stops. This can cause 2-D content that is projected through the XL unit using a non-3-D output, such as the pre-show output, to appear soft.

Posted by Eric Robinson (Member # 2966) on 01-25-2012, 12:10 AM:

This is an XL unit.

Apparently this is only affecting the preshow. The 3D feature following has good focus. Nora from RealD sent me a manual so I probably just need to RTFM.

Thanks for the tip on knocking alignment out with rough treatment.

Posted by Stefan Vogels (Member # 5573) on 01-26-2012, 04:59 PM:

The RealD XL unit has 3 settings which you can change. You can adjust the size of one of the images, you can allign left / right and up / down of the images. There's also an locking mechanism which needs to be loosened before adjusting ! Use the cross Hatch test pattern to allign.

Best Regards