Mitsubishi DLP RP WD65C9 - Gray shadow in top corners?

pluvious · Post by **pluvious** » Fri Jun 04, 2010 12:11 pm

Hi all, just joined with a question. I took advantage of a $899 sale at Fry's for the MITSUBISHI WD-65C9 65" DLP set. When I got it delivered and set up I noticed with a white screen, dark shadows on the top right and left corners. I'm not sure if I have a defective bulb or need to get it exchanged. The "AVS" forum claims this is 'normal' and ALL sets have these dark corners. I doubt it, check these pictures.

I can even make out a dim halo in the center of the screen kinda like a flashlight effect. I've crudely circled the areas in the second shot.

[img]http://img39.imageshack.us/img39/7025/examp1.th.jpg[/img] [img]http://img517.imageshack.us/img517/7702/examp1a.th.jpg[/img]

You can hardly see the dark areas with normal shows, but white screens really make it obvious. Should I exchange it?, request a new blub, or just not worry about it?

Richard · Post by **Richard** » Sun Jun 13, 2010 7:06 pm

The problem you have shown us is a uniformity error. That means the light output is not the same at all places on the screen. Many displays suffer from this, especially LCD flat panel. The key issue at hand is how noticeable it is and of course a full white field raster will make this obvious as shown in your pictures. I am reminded of the LG press event at CEDIA with a room full of new LED back lit displays and for about 30 seconds during the program material every one of them had a white field raster showing obvious uniformity errors on every one of them! Uniformity errors are difficult to see with everyday images.

I can't tell you if the error you are experiencing is normal without checking it out myself. My gut tells me though this level of error is excessive and does not meet manufacturer specs. The easiest way to prove it is to go the store with an image on a DVD similar to what you have (or a calibration DVD that would have this test pattern) and see if the store displays show the same problem. You will get your answer...

Please provide feedback on what you found out... there is a possible design reason for this error...

pluvious · Post by **pluvious** » Mon Jun 14, 2010 2:49 pm

Hi Richard and thanks for responding to my post. In the week since the post I've been looking at it very carefully and I think I'm being overly critical. In fact, it seems to have been just a simple angle issue. When I center myself at the proper height those dark corners are not visible. Even on a white screen.

I also ran a BluRay calibration disc called "Spears & Munsil" and did not notice any serious problems that I could tell. Of course I'm just a layman. I'm sure a proper professional calibration tech could tweak it even further. I had to crank down the contrast from pegged down to 42 or so and I had to lower the sharpness quite farther then I expected based on some 'ghosting' in the cross-hairs.

I guess it all came down to not being used to a DLP projector set, I've been spoiled with my 42" Plasma in my bedroom and seeing a uniform sharp, bright picture. The DLP seems to be extremely picky with angles since it's such a big set. I'm probably sitting to close which doesn't help either. (7'-10') The stand I have it one raises it a bit to high for my taste as well. I'm going to chalk it up to viewing angle and let it be.

Besides.. I only got if for my 77 year old Mother for the living room... she has no clue what I'm worrying about and thinks it looks "great".

Richard · Post by **Richard** » Tue Jul 06, 2010 7:49 am

I had to crank down the contrast from pegged down to 42 or so and I had to lower the sharpness quite farther then I expected based on some 'ghosting' in the cross-hairs.

Use NATURAL mode and leave the contrast full blast. Sharpness is a feel good control that technically should not exist!

The DLP seems to be extremely picky with angles

All rear projectors have always been that way. LCD has angular viewing problems as well, just differently. Only plasma provides extremely wide angles without any loss.

Both LCD and RP products are at their best when the viewing position puts your head in the middle of the screen without any angle.

pluvious · Post by **pluvious** » Tue Jul 06, 2010 11:00 am

Thanks for the followup. I ended up exchanging the set with another and the problem seems to have been reduced. The new one seems a lot brighter and more uniform. I had turned down the contrast based on the Spears and Munsil calibration disc. But I will see how it looks cranked back up. (I have it at Natural as well.)

Thanks again!