Red and blue specks

[burstingfist]

I just noticed that the projector I am using has random red and blue specks all over the image. What is causing this? Is this dust? I have never noticed it before, but it is subtle. Now that I see them, I want them gone! Any help is appreciated...

[InsideUsAll]

I have a similar problem with one of our lcd beamers. except mine are green dots. I have been told by the manufacturer infocus that it is probably dust. But I have had the thing in bits and give it a really good clean, but the dots still appear. Worrying thing is they appear to become more obvious after a couple of hours running. I suspect they are dud pixels, which stick on after a while on my green lcd panel. :confused:

[Yetimon]

Most likely dust particles on the LCD panels. A good way to test this is to project an image and get the focus spot on. Then project a compleatly white picture, and pull the focus back and forth a bit. You should see the red/green/blue specks come into focus at a different point to the image. This is due to the dust particles sitting at a different distance to the lens than the LCD panels.

Open up the projector, and with it still beaming the white image, CAREFULLY remove the dust particles with a clean cue-tip. Do not press too hard on the panels - you don't want to bust them! :) You should be able to see the results in the projected image as you go.

If the specks are focused at the same point as the LCD panels, and if they are exactly the same size as a pixel, then yea - you've got dead pixels.

BTW - the internals an open projector in a smokey room makes for some very pretty close-up video camera pictures - just make sure it's a crappy old projector that you don't care too much about (smoke + hot LCD panels don't mix)

Cheers!
-Yetimon

[burstingfist]

Thanks Yetimon, that's what I figured, I just haven't inflated my balls large enough to actually mess with the projector at such a low level (it's my friend's company's projector). I just need to buy some Q tips and do it. It needs to be done though, there is quite a bit of dust in the bastard. You are the first person to offer me a real world solution to this problem, therefore, you rock!

Thanks

[charlielangridge]

Rember people, never blow on electronic components, the moisture kills them. Use spray air (xpensive but needed) and if you touch any opticals (lamps, lcds, etc) cleen with alcohol (recomend: hard disk cleaner) otherwise it will considerably shorten their life!