Mitsubishi 2007 (and possibility '06 & '08) lens cleaning procedure. No more halo's. - Page 9

The name of the picture has the words In-Focus in it. I think there is a brand of projector with that name. The assembly is more compact than in a Mits TV, so a projector might make sense.
Also, there seems to be a lens between the mirror and the chip, probably to shape the light beam before it is directed onto the chip. If there is a comparable lens in the Mits LE, it is probably between the color wheel and the mirror, because there is nothing in my LE between the mirror and the chip or projection lens.
I didn't make any effort to look into any other part of the LE other than the projection lens. Maybe next time.

Did you disassemble your set again, or are the new photos from another time or set?

What technique do you use to embed the photos in the message? I didn't see anything other than the choice of attaching a picture.

When you finished cleaning the lens, was there problem remaining that made you think you didn't get it all?

When I got through, things were a lot better, but we still noticed some blooming around text in movie credits pluss the poor black level to left of center. In our case, I'm not sure that the text problem isn't in our own heads, caused by the small cataracts we both have. I could get up close to the screen and evaluate it with a magnifying glass, but it wouldn't change the fact that I'm not touching it again until next winter at the earliest. In the mean time we will just live with it. Maybe I'll have more guts next winter and do more than I did this time.

If you don't have a calibration disc and have a PC attached to your TV, the free program monitortest.exe provides an excellent way to generate screens to further evaluate it. In my case, it wasn't necessary because the black screens we often see in the normal viewing really told the tale accurately. All the program did was to verify that what we were seeing wasn't due to the program material.

Re the photos, that makes sense. I used to do something similar with photos in my eBay auctions. I suppose that means if you ever quit your online storage account, the images are gone. That method does produce some excellent images though.

Hey All,

Just did the cleaning for the second time and I'm wondering if I did something wrong...the dark areas seem really dark and I'm having to run the brightness and contrast higher than I did before. I'm trying to decide if that's just because I was used to the picture with the film on the lens and the blacks are just much blacker now or if I messed something up.
I have an Oppo BDP-93 and I popped the Spears & Munsil test disc in to check it. Using the brightness test pattern I adjust it to where the User's Guide says it should be. I also have a test pattern on my DirecTV DVR that I checked and again, I set it up correctly on the pattern. It just seems that when I watch a BR or HD programming the dark areas are much darker. I feel like I'm missing some details. Am I seeing black crush or just better blacks? Also, why would I need to run the brightness higher than before? Am I just used to the 'film' over the entire picture and now it looks the way it should? One last thing I'll mention is that the film was worse this time than it was the first time I cleaned it....
Sorry, I know I kind or rambled there but any input would be great.

Thanks,
Jeff

This is exactly what I was seeing on mine. Bruce, did you see anything like I described in my post? The more I look at the picture, the more I think it's just really phuking good and I'm not used to it

Yep, you're right. I just got the Oppo about 2 weeks ago also so that probably has something to do with it. I just didn't remember the PQ improvement being this dramatic last time. Watched 'Alien' and 'The Bourne Identity' last night after I posted and with some minor tweaking really got it dialed in...I can now say that the picture is truly stunning...
I am kind of curious as to why, like yours, the fog on the lens was worse this time than it was the first time with less hours...did the first cleaning (and replaced the bulb) at ~3000 hours. I haven't checked the clock yet but I would guess that it can't be more than 5000 now.
Anyway, thanks for the feedback and again, thanks for the tutoral...

-Jeff

Since we normally watch the Mits TV at night in a dark room, the low black level and brighter streak left of center is particularly noticable. It probably wouldn't be as noticable if we watched it during the daytime in a brighter room.

I believe that the reason for the lower dark levels compared to when it was new is due to deterioration in the coating that is supposed to absorb the light that is reflected off the chip when a dark pixel is commanded.

The same vapor that coats the lens and compromises the image also condenses on the black coating in the compartment that is supposed to absorb the light. I doubt that the coating can be cleaned, like a lens surface, but maybe it can be recoated. Maybe between now and next winter we will come up with something worth trying.

What do you think?

VB,
I agree that there can be some softening of the image if the mirror and screen above the Light Engine is contaminated, but when I took the screen off, before I tackled the LE, I found that compartment very clean and dust free. It might make sense to clean the back of the screen and the mirror, but I don't think that there is a need for any kind of light absorbtion or special black light absorbing coating in the compartment behind the screen, other than the black plastic that forms the compartment.

Once you get beyond the projection lens, all of the light is directed at the screen. There isn't any part of this light that has to be absorbed, unlike that diverted by the micro-mirrors in the LE. I've convinced myself that the steak left of center on our set is due to a bad light absorbing coating within the LE, or maybe light scattering off of the micro-mirrors that are supposed to be tilted out of the way.

When/if I crack open the LE again, I'm going to try to find a way to clean the MD chip (as well as clean/refresh the light absorbing coating). If the MD chip runs hot enough, it may be unlikely for it to pick up some of the vapor that condenses on the bottom of the projection lens, but any particles or coating that settles on the MD chip is going to make things worse. I generally don't like the idea of using compressed gas to remove particles; it is just as likely to drive them deeper into places you don't want them in the first place. Maybe T.I. or one of the projector manufacturers has some recommendations on cleaning the surface of the chip.

It sure would be nice to know what I was doing BEFORE I tackle something like this, but I guess that's the price of being an amateur. Thankfully I had your instructions to get things started.

So much for my theoretical analysis. I wouldn't have expected it would be much of a problem. But I suppose any time light gets scattered to where is doesn't belong, it's a potential problem.

The environment in the house here is pretty clean. No smokers, no pets, no kids, but the urban air is dirty. The only way for me to get into the compartment behind the screen is to remove the screen, and I didn't even see much dust on the projection lens. I am especially good at posponing things and this one is going on hold until next winter. I'll keep an eye open here if there are any breakthroughs.

I cleaned my WD-57831 again this weekend and WOW what a difference it makes.

This is the second time I've cleaned it myself after having the LE replaced under warranty the first time the blooming showed up.

The lens wasn't as coated with film this time and was easier to clean. I waited almost 2 years between cleanings (It started needing it about 9 months ago).

Thanks videobruce and everyone who posted info on how to do this yourself. It gets easier each time I do it and I get the picture geometry better every time (getting a bit more confident).

Not true. I have a WD 65732 and when my first lamp died, it definitely did it slowly over a few months. Eventually, at about the time I really noticed I had to increase the brightness and contrast to get a good picture, then it died outright. Everything was significantly brighter once the bulb was replaced.

But there is no question that the bulb lost its intensity slowly over time.

Of course, now my new problem is that the heat inside the bulb housing has damaged the wiring to the extent that the bulb won't come on any more. Ballast is firing and I can see little blasts of light, but the bulb won't come on. This time I have a new bulb WITH housing on its way overnight.

And I do believe I will take the plunge and pull everything out and clean it...

I think source material comes into play here to a certain extent as well. I notice that when I watch programming on CBS (local affiliate is KTVT via FiOS) the picture isn't as bright as say a Blu-ray from my Oppo BDP-93. Local news on the ABC affiliate is bright and particularly sharp.

I make sure to keep the air flowing by pulling the lamp assy out and inspecting for blockages every now and then. I think we should all read this post by Cap'n Preshoot as a reminder of how long the lamp will last with proper ventilation: http://www.avsforum.com/avs-vb/showp...postcount=2552

He does mention that his picture had become dark, but nevertheless over 8000 hours is pretty darn good.

Alright, so an update is in order...

New bulb and housing are in place and the TV fired right up. The heat damage inside the housing was definitely the culprit.

Put the TV back together and waited for the right time to do the cleaning.

Moved the TV out to a table in the kitchen and went to disassembling. Instructions are intuitively easy. I found exactly as described - some kind of hazy deposit on the interior lens below the iris. Cleaned up nicely. Still have to wait to put the TV back in place, but we were definitely seeing the haze pretty clearly on the white on black credits, so I'm confident my picture will be much improved. This is the first cleaning since we bought the set back in 2007.

Anyhow, the only issue I have is the shape of the picture. I was able to make adjustments in the service menu and with the adjustment screws, but the top of the picture is still bowed upwards about 1/8" to 1/4". Not a big deal, but there is no adjustment for that. Of course as I gently push and pull on the outer frame, I can get the picture to move, so it may just be a matter of the imperfect structure of the outer shell.

Good going deadrody. If you had a hazy lens before, and a clean lens afterwards, you're in for a real treat. Your efforts will be rewarded. I can't speak to your picture geometry issue since I had no such problems after I was finished. I must have gotten lucky because the picture fit was the same as before pulling the LE out. Good luck. BTW, my set will be 5 years old next March.

hate to dig an old thread but i wanted to post my results

its a 65831 that i tried to sell on craigslist for months, now i think i'll keep it. thank you very much to all who contributed.

I still have my original bulb with over 14,000 hours and I replaced it because the picture was dim. installed a new bulb and holy crap. I had to turn down my contrast and brightness down a lot. New bulb has 400 hours or so.

I'm afraid I need to get my guts up and take on this challenge; I've been underwhelmed with my PQ and noticing glow around white text...

The testimonials don't lie BadClams. Do it and you won't regret it.