Color Issue after cleaning Epson 3100


Hi all,

I disassembled my Epson 3100 projector and did a thorough cleaning of every optical surface I could. The only ones I am not sure of are the sides of the LCDs facing the glass prism block thingy. There was some type of filter between the two, I used pipe cleaners and lens cleaning tissue wrapped around thin cardboard to do what I could.

This was my first time taking a projector apart and I read what little I could find online about what not to do so possibly I could avoid disaster. Before the projector was all but unwatchable. It was getting dark and had color uniformity issues. Large areas here and there on the screen was tinted pink or cyan.

After getting it back together and plugging it in I was like “Wow!” That looks as good as new… and I know the bulb has at least 1500 hours on it! My biggest concern during this entire process was leaving behind something that would show up as spots on the screen. But looking at a completely white or black image it is pristine.

But, and seems like there always is a but. I have lost that nice deep red on the upper portion of the screen. So as I go vertically down the reds get better, as I go up they turn more orange. When watching video it doesn’t really show, but in PC mode things I know should be red are more orange.

I have a second twin to this projector that needs to be cleaned as well, but before I do I would like to understand more about this color issue and maybe some theories as to what I did to it.

Anybody have any thoughts or suggestions that could help me out?



so, you're saying that after cleaning what was red now looks more orange at the upper part of the image? Can you post a photo of the issue? What you're describing could be some issue with the polarizer filters (resulting of the cleaning, which has happened to me when I used distilled water one time), or, if it's a regular loss of red, a misaligned optical element.

From my experience, the best way to clean LCD projectors is to remove the optical block completely and use compressed air in a tangential direction to the surfaces you're cleaning; and a moist filter should be used at the front of the air compressor hose. Moreover, my experience also tells me to never clean what already looks clean.

Now, I wonder why the projector was looking so bad before the cleaning. In most cases, these projectors can get dust blobs on the LCDs (mostly visible on dark scenes) and also a dimmer light because of dust on the optical elements, but it shouldn't be that much that it would make it all but unwatchable, as you described.


Thanks for the reply. I run my projectors a lot and smoke so that probably is what is causing them to become dirty. Instinctivly, I know I shouldn't clean anything that already looks clean. I learned this when I was into photography years ago. It really had become all but unwatchable before and I just couldn't resist the urge to clean everything while it was apart. This is going to be great learning experience for me and when I do my next one I should be more successful.


I haven't ruled out a miss aligned lens. As you know there are several in it, but one just didn't seem to hold itself in place like the others. Like it was missing a holding piece and kept falling out. My second projector isn't near as bad as this one was so I think I will see what compressed air will do for it. There are air ducts that blow directly from the bottom up at each of the polarizers/LCD blocks. I expect this is where all the dirt is accumulating. The part with the dichroic mirrors and other lens is fairly sealed.

Viewing the my screen, it is much more apparent with the white background versus the black..

Thanks for your help!
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Looking at the photos, it seems to be a worn out polarizer filter. It happens because of the heat generated by the projector, especially if running lots of hours in a daily basis. The only solution is to replace the worn out filter. Those filters sit between the light path and each LDC panel.