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Topic: Brightness Uniformity
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Joined: Sep 28, 2017
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Has anyone experienced brightness uniformity issues with their DLP projector? I own a BenQ HT2050 projector and always run it in SmartECO mode to help prolong bulb life as much as possible, and keep the lens clean at all times. Anyways, I recently mounted this projector on a wall mount behind the seating area. It is inverted when on the mount. This would put it about the same height as when using a ceiling mount. After doing this, there was a noticeable brightness uniformity problem on the front wall the image was projected onto, with the left side being much brighter than the right side (which was darker). I then placed the projector, right side up, on a laptop stand right behind the seating area. The projector's height was about slightly above the back of the couch. This time brightness uniformity was a lot better, and a lot more even. You can notice slight more brightness on the right side of the wall and little darker on the left side, but it is not very noticeable or distracting when watching content. The projector was exaclty in the same place - direct center - when either on the wall/ceiling mount and when on the stand. Can someone explain why this is, and has anyone exerpienced this before? Is there anything that can be done to help brightness uniformity when the projector is on the wall mount? Thanks very much
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Joined: Mar 28, 2005
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This doesn't sound like normal operation and may indicate that there is something wrong/loose inside the projector. It could be the light tunnel inside or it could be loose optics that are shifting when you move the projector around.

I would be hard pressed to give you an exact answer but I would reach out to BenQ for support. If this is outside of warranty, then it's a tough call to make as they likely will want it in for evaluation and repair, which may be more costly than the projector is worth.

Definitely not a normal issue for most projectors, and it should be noted, that in the HT2050 review, it was actually called out that the right side of the image had a pretty significant brightness falloff...

https://www.projectorcentral.com/benq-HT3050-HT2050-projector-review.htm?page=Picture-Quality

"On our HT2050, brightness uniformity is also less than great, but in a different way. The picture is brightest in the lower center and it fades most to the upper left instead of the right. On this unit the fading is incrementally progressive across the image, so it does not produce a vignetting effect, but the upper left corner is 40% less bright than the lower center."

This may be what you are seeing, but I think that it is still a flaw in the design itself as this much image non-uniformity is not normal.
AV Integrated - Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.
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Here are some photos that I took showing the brightness uniformity. When the projector is in the "front" position (front of the screen, on a projector stand), the screen is brighter on the right side. When the projector is in the "front ceiling" position (front of the screen on a ceiling mount), the screen is brighter on the left side

Attachments:

Front position

4032 × 3024 pixels (182.09 KB)

Front ceiling position

4032 × 3024 pixels (167.40 KB)