Film-Tech Forum ARCHIVE: NEC NC2500S image distortion

This is topic NEC NC2500S image distortion - red blocks / bands across image in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Jason Raftery (Member # 6291) on 11-12-2013, 12:19 AM:

I'm running into a sporadic problem with a handful of 4 or 5 year old Series 1 NEC NC2500S projectors where a show will start and the image will have a green hue that is overlaid by numerous red blocks and bands.

Here are a couple of examples from two different machines:

And a video clip: http://www.youtube.com/watch?v=MECpF9xX6Zo

The problem appears to happen at random, regardless of aspect ratio, color space, when the machine was last power cycled, time of day, etc. The problem is always resolved by rebooting the projector. Once gone, a given machine can go weeks or months without a re-occurrence. In no case have the projector logs offered any clues as to what is happening here.

The problem has not been observed on machines that originally shipped as model NC2500S-A. Projectors are on the current TI / NEC firmware. The problem does not seem to be related to the interface board as one of the affected machines has had Type 3, 5, and 6 boards put in it and still experienced the same problem. Servers are GDC SX-2001As.

Any idea what the culprit is? Is this a common issue as this model projector ages?

Posted by Marco Giustini (Member # 4544) on 11-13-2013, 03:41 PM:

When the corruption happens, can you try some test patterns from the projector? If corruption is seen on test patterns, try calibration patterns. That should tell you where the problem lies.

Make sure you're running the latest SW (not too familiar with NEC series 1) and it may be worth reseating everything that can be reseated - but you need to know what you're doing.

Posted by Jason Raftery (Member # 6291) on 11-14-2013, 12:22 PM:

Some degree of corruption was visible on a solid red pattern on the machine where this happened in front of me. A solid white, solid blue, and cross hatch pattern were fine, however. All our 2500S and 2500S-A machines are on TI 15.1, NEC firmware 2.11 and NEC data version 2.16.

Posted by Marco Giustini (Member # 4544) on 11-14-2013, 04:33 PM:

You are on the latest software.

If you see corruption on a test pattern, then the problem lies in the projector.

I am not sure where the RED pattern is generated on a series 1, I guess if it was the uncorrected one it was generated on the formatter itself? Maybe someone else could be more precise.

On a series 2 I would recommend reseating the boards and the light engine umbilical cord, and maybe the connectors on the formatters as well. But first we need to assess where the RED test pattern was generated: if it's generated on the formatter I guess you'll need a new light engine - or a new formatter, but I'm not sure NEC is supporting it on the field.

Posted by Gordon McLeod (Member # 33) on 11-15-2013, 11:00 AM:

Check the cables to the Light Engine some of those ribbon cables can get poor connection issues and they are very fragile