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Discussion Starter · #1 ·
I just noticed that there are green circles on the screen when I press pic mute or display black screen. Diameter of circles is about 2-3 inches (picture size 100 inch). When I turn focus ring circles became small but very bright green dots. I counted about 25-30 small dots. When picture is in focus I can see only less than ten cirles on the screen.


My quess is that these are dust blobs but how this is possible? HT1000 is supposed to have sealed optics. I tried to look lens while projector was on and I was able to see a lot of small dust particles inside lens. There are only few hours on my unit so far. Is sealed optics only marketing trick or is there something wrong with my unit?
 

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My HT1000, before I returned it, had a dust blob (or two?). With a black image, I could see 3 dark gray circular "rings". When I looked into the lens, I could see a large speck of dust behind the lens in the center, and quite a few little ones. Also, there was a slight color uniformity problem, like another HT1000 owner had. There was also slight pincushion. And, after 18 hours, the fan started rivalling my HTPC in fan noise!


I suspect quality control on the HT1000 is lacking a little bit (guitarman went through THREE HT1000s before he got one without a stuck mirror). There may also be an issue with overly-soft focus (could be related to dust blobs), although impossible to tell at this point since no dealer in Western Canada demos an HT1000.


My NEC LT240, on the other hand, is nearly perfect. No dust blobs. No color uniformity issues. Tack-sharp focus. Perfect geometry. Fan can sometimes be noticeable, but not as bad as the HT1000 I had. What the hell...you'd think they'd be more careful with the HT1000?


Both the LT220/240/260 and the HT1000 have sealed optics. That means that you're stuck with the dust you've got. At least no more crap can get in! If I had kept my HT1000, I'd have had NEC clean the optics, fix the focus, replace the fan(s), and remove the pincushion at full zoom (although maybe that is a side effect of the iris).


Of course, this is nothing compared to what the Sharp Z10K people are dealing with. :D
 

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Discussion Starter · #3 ·
Quote:
Originally posted by maxleung
Both the LT220/240/260 and the HT1000 have sealed optics. That means that you're stuck with the dust you've got. At least no more crap can get in!
So all dust that is inside my projector has gotten in at factory. Or maybe there is something wrong with the optics because it seems very hard to get uniform focus. Upper part of the picture is softer than the lower part when I set focus as sharp I can. Is this manufacturing fault and I can get it fixed/replaced by instacare?
 

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Good question tk. Now that you mention it, I did notice that focus was a bit off at the corners on the HT1000 (relatively common on projectors it seems). My NEC LT240 was better in that regard. I doubt dust blobs would affect focus on the corners, it would suggest an optical problem.


I don't know if NEC will take care of that, but you could ask them to adjust the focus while you have them clean the optics (a local HT dealer told me to have NEC do that if I had elected to keep the HT1000). Have you checked the color uniformity? The blue screen when you first turn on the projector is a good check. My HT1000 had a color uniformity issue on the bottom left corner.
 

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Contamination inside the sealed light engine was my main problem with the HT1000.


I received (2) replacement projectors that were worse than my original. So I ended up sending in my original to be cleaned and the software updated.


When the projector came back, the original dust blobs had not been corrected.


Using the service manual, I ended up cleaning the light chamber myself. The process is very easy if you have a clean environment to perform the service.


I suggest you contact NEC customer service about the focus problem which does not sound right. Then also have then clean the light engine when the service the focus issue.


NEC amy simply replace your projector, but their policy has varied regarding what problems trigger an instant replacement.


If you would like to service the HT1000 light engine yourself down the road, let me know.


RJ

...
 

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Discussion Starter · #7 ·
Thanks for your comments guys. Very valuable information.

I'll try to contact Nec and ask what to do.

I noticed that focus was better when zoom was in tele position and it goes worse in wide.


jmschnur, Iris did not affect focus (if that's why you mean by aperture).


Bytehoven, you have opened your projector. How dust proof this sealed optics really look like? Is there any openings from where dust can get in or is it really 100% sealed. Is it possible that dust goes between the lamp and the glass where light goes in to light engine (or is there any protection between lamp and light engine)?


maxleung, color uniformity looks pretty good to me. It is not 100% good in corners but very close.


Do you guys have any information about does HT1000 support deinterlacing for PAL too? Is there PAL film mode (2:2) also?
 
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