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I'm poor so I bought an old NEC LT380 1024x768 LCD projector off Craigslist for cheap until I can get a modern 1080p projector. Being a novice, I didn't notice some things while speedily checking the thing out.
1) If I focus towards the top, the bottom becomes unfocused. Eventually I realized the top-left seemed to oppose the bottom-right corner. If I focus toward the center, the picture blurs outward and moreso towards those directions than the other corners. It has me imagining something angled diagonally so that one corner is further while the other is nearer.
2) Slight yellow tint. Came here and learned about LCD projectors and the faster degradation of blue polarizers that seem to typically become noticeable after about 5000 hours of usage (which mine happens to be at).
3) Slight red-ish edge on picture appeared first at the top, then moved to the right side of the picture. EDIT: I did my homework there, too, and learned this is very likely dust on the polarizers or lcd panels and has been remedied by many with a compressed air cleaning.
So, I decided to open up the projector and clean everything. I'm unwilling to invest more money into an outdated projector not even ideal for movies, and buying one for parts seems pointless as it would likely be just as used up. Whatever is the picture I can get with a cleaning is what will do until the day I can get a new one.
Unfortunately, as seasoned people may see, I messed with the LCD panels on the optical block. So, after doing some video watching and forum reading, I have determined I'll employ forceps to tediously rectify my error and get the red, green, and blue back in place since unfortunately, the LT380 does not let me have easy access to the panels while it's out. I haven't gotten to test it out as its colors are all zonked out, but I think I haven't noticed a red-ish edge...
Now, since I have it open, the last thing I can't figure out, is what the hell could be causing the uneven focus, and if there is any way for me to fix that. I found a couple threads here on the issue. First order of advice is to make sure the projector is completely perpendicular and centered and all that to your surface. I have tried tilting and angling every which way and I see no change in the uneven focus. I followed the next advice and held up a paper and brought it closer to see if there was actually an uneven focal point. Unfortunately, it seems so (see pics). I recall someone saying that it could be something situated incorrectly with the optical block. In my pics, the picture is focused to the bottom-right corner while the paper is a few feet closer, - about 75cm/29.5in from the projector.
Can someone offer any ideas of what would cause this and how to fix it? So far, I've been unable to spot anything on my own. It's really the last blemish to this purchase and of course it would be nice to get to watch a sharp picture and not a hazy one. I don't even mind the possible slight yellow tint as it seems like I could correct that with the video card settings on my computer.
In my cleaning, I opened up the compartment with all the mirrors and color filters, wiped all of that, blew compressed air at all of it, cleaned every lens, filter, or similar type thing. I separated the optical block from the lens and was only able to open one layer of the projector lens and cleaned it but couldn't figure out how to go further (and was wary to).
Help a ripped-off poor guy out. Please!
I'm poor so I bought an old NEC LT380 1024x768 LCD projector off Craigslist for cheap until I can get a modern 1080p projector. Being a novice, I didn't notice some things while speedily checking the thing out.
1) If I focus towards the top, the bottom becomes unfocused. Eventually I realized the top-left seemed to oppose the bottom-right corner. If I focus toward the center, the picture blurs outward and moreso towards those directions than the other corners. It has me imagining something angled diagonally so that one corner is further while the other is nearer.
2) Slight yellow tint. Came here and learned about LCD projectors and the faster degradation of blue polarizers that seem to typically become noticeable after about 5000 hours of usage (which mine happens to be at).
3) Slight red-ish edge on picture appeared first at the top, then moved to the right side of the picture. EDIT: I did my homework there, too, and learned this is very likely dust on the polarizers or lcd panels and has been remedied by many with a compressed air cleaning.
So, I decided to open up the projector and clean everything. I'm unwilling to invest more money into an outdated projector not even ideal for movies, and buying one for parts seems pointless as it would likely be just as used up. Whatever is the picture I can get with a cleaning is what will do until the day I can get a new one.
Unfortunately, as seasoned people may see, I messed with the LCD panels on the optical block. So, after doing some video watching and forum reading, I have determined I'll employ forceps to tediously rectify my error and get the red, green, and blue back in place since unfortunately, the LT380 does not let me have easy access to the panels while it's out. I haven't gotten to test it out as its colors are all zonked out, but I think I haven't noticed a red-ish edge...
Now, since I have it open, the last thing I can't figure out, is what the hell could be causing the uneven focus, and if there is any way for me to fix that. I found a couple threads here on the issue. First order of advice is to make sure the projector is completely perpendicular and centered and all that to your surface. I have tried tilting and angling every which way and I see no change in the uneven focus. I followed the next advice and held up a paper and brought it closer to see if there was actually an uneven focal point. Unfortunately, it seems so (see pics). I recall someone saying that it could be something situated incorrectly with the optical block. In my pics, the picture is focused to the bottom-right corner while the paper is a few feet closer, - about 75cm/29.5in from the projector.
Can someone offer any ideas of what would cause this and how to fix it? So far, I've been unable to spot anything on my own. It's really the last blemish to this purchase and of course it would be nice to get to watch a sharp picture and not a hazy one. I don't even mind the possible slight yellow tint as it seems like I could correct that with the video card settings on my computer.
In my cleaning, I opened up the compartment with all the mirrors and color filters, wiped all of that, blew compressed air at all of it, cleaned every lens, filter, or similar type thing. I separated the optical block from the lens and was only able to open one layer of the projector lens and cleaned it but couldn't figure out how to go further (and was wary to).
Help a ripped-off poor guy out. Please!