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

post #241 of 386
Quote:
Originally Posted by videobruce View Post

Interesting photo. Good find. I wonder what set this was taken from?

I assume that is the color wheel to the right, the DMD device at the bottom. I also assume the light path is to the rear of the main lens (black) with the interior lens behind it along with the internal mirror.

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.
post #242 of 386
Thread Starter 
Front projector. No wonder why this assembly is so large.
post #243 of 386
Thread Starter 
I added additional pics of the ballast assembly (post 9) & the internal lens assembly mirror (post 5) which I did not dissemble the 1st time. After 4300 hours, I didn't find any 'haze' on either the mirror or the two lenses.
post #244 of 386
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.
post #245 of 386
Thread Starter 
Yes, the 'halo' issue was now visible unlike the 1st time where I dissembled it mostly to see what the lens looked like and to document the steps for the procedure. As posted, there was a slight haze, but I didn't notice it on screen. This time it was twice as much, possibly more, but on screen it was really distracting. It wasn't just a halo around text (white on black movie/program credits for example), but a bright haze in darker portions of scenes that had a very high contrast: shots with a window in the background, outside in the shade on a sunlight day looking past thew shade if you can picture those.

5/09 2200 hrs; not noticeable on screen,
4/11 4340 hrs; very noticeable.

Looks like every 18 months is a good time frame since I started noticing this in the past 2 or 3 months
post #246 of 386
Thread Starter 
I uploaded them to a file/photo sharing/storage service. Photobucket in my case. Instead of attachments that you have to open one at a time a (or in separate windows), these are embedded in the thread, easier to see, but more of a hassle to produce since you have to go through the trouble of uploading them elsewhere, labeling them and then copying the URL to your post.
post #247 of 386
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.
post #248 of 386
Thread Starter 
Quote:


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

Actually, I did it different this time that I will never do again. I lightly sprayed into the opening, apparently too much. I should of just dropped a coup[le of drops of lens cleaner on the lens. What was left behind in the corners where I couldn't get to (off the lens) vaporized the first time I turned the set back on to a point I thought I was in a London fog. It was a one time thing. The next time, all was well.

Using a 100% window from a test DVD or a signal generator will produce a slight 'glow' directly around the 'hot spot' of the pattern. This is a RPTV 'thing' due to internal reflections.
Quote:


if you ever quit your online storage account, the images are gone.

Or if you delete the images. I see it all the time. Posts with blank spaces where an image was suppose to be.
post #249 of 386
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
post #250 of 386
Quote:
Originally Posted by videobruce View Post

Yes, the 'halo' issue was now visible unlike the 1st time where I dissembled it mostly to see what the lens looked like and to document the steps for the procedure. As posted, there was a slight haze, but I didn't notice it on screen. This time it was twice as much, possibly more, but on screen it was really distracting. It wasn't just a halo around text (white on black movie/program credits for example), but a bright haze in darker portions of scenes that had a very high contrast: shots with a window in the background, outside in the shade on a sunlight day looking past thew shade if you can picture those.

5/09 2200 hrs; not noticeable on screen,
4/11 4340 hrs; very noticeable.

Looks like every 18 months is a good time frame since I started noticing this in the past 2 or 3 months

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
post #251 of 386
Thread Starter 
Quote:


the dark areas seem really dark and I'm having to run the brightness and contrast higher than I did before

Quote:


The more I look at the picture, the more I think it's just really phuking good and I'm not used to it

You were just use to the bleached out look caused by the scattering of light against that lens.
post #252 of 386
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
post #253 of 386
Quote:
Originally Posted by videobruce View Post

Using a 100% window from a test DVD or a signal generator will produce a slight 'glow' directly around the 'hot spot' of the pattern. This is a RPTV 'thing' due to internal reflections.

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?
post #254 of 386
Thread Starter 
I beleive it is just light scattering around the area on the screen itself.
Just as a similar effect would be on a front projection screen, slides or movies.

If this black coating deteriorated, the absorption would decrease, increasing the halo effect wouldn't it?
post #255 of 386
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.
post #256 of 386
Thread Starter 
Quote:
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
Nothing is 'air tight', so dust will settle on horitzontal surfaces. AFAIC, unless there are smokers in the household, I don't see any need to remove the screen(s),. Considering there is way too great of a chance of damage and/or things going wrong, especially with larger screens (over 50").
Quote:
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.
I don't remember which manufacture (Hitachi maybe) 5 to 7 years ago, but at least one had issues with light scattering inside the compartment. So much so, there were posts on adding some type of treatment to the inner surfaces to solve the problem.
post #257 of 386
Quote:
Originally Posted by videobruce View Post

I don't remember which manufacture (Hitachi maybe) 5 to 7 years ago, but at least one had issues with light scattering inside the compartment. So much so, there were posts on adding some type of treatment to the inner surfaces to solve the problem.

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.
post #258 of 386
Thread Starter 
Thanks to rich3fan for the following:
Quote:
Originally Posted by rich3fan View Post
...And the results are amazing. I knew when I turned on my Blu-ray player and no longer saw a white glow around the white text logo on a black background that the cleaning was well worth the effort and anxiety. I was actually contemplating replacing my DLP TV with a plasma because for about the last year or so I was becoming quite disappointed with my TV's picture quality. No more. Everything about the picture from detail to color quality is such a major improvement. Black text on white backgrounds is bold and well defined. I could go on and on but it's mostly already been said, so I'll let the pictures do the rest...

The patient:



The operating table:



This picture of the lens before the cleaning is a bit blurry as this morning's caffeine was coursing through my veins, but I think the haze is detectable:



A picture with lens cleaning fluid applied:



And finally, the after:



And the consumables used:



It took 10 of the double-sided q-tips along with 5 Kim-wipe lint free cleaning wipes to get the lens clean. That was the tough part. I don't know if it's because of the cleaning fluid or the lens surface, but it was difficult to get all of the streaks removed, and it seemed like the fluid took forever to dry, but again, very much worth the effort.

I now have renewed faith in the picture quality of my TV, and yeah I think I'll keep it.

A big thanks to videbruce for his effort in detailing this cleaning procedure. <- = thumbsup!
post #259 of 386
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).
post #260 of 386
Quote:
Originally Posted by videobruce View Post

I never heard of a non CRT RPTV (or any other) that was that dark. Is this in a bright room in daytime or a light controlled room?

When the lamp dies, it dies, there is no middle ground. Have you 'tweaked' the set yet?

BTW, welcome to the forums (and your girlfriend did the right thing).

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...
post #261 of 386
Thread Starter 
Quote:


Everything was significantly brighter once the bulb was replaced.
But there is no question that the bulb lost its intensity slowly over time.

From my experience, around 300 hours seems to be the period where the lamps output stabilizes from very bright to an average output.
Past somewhere around 3-4k hours (just a guess), the output makes the "Natural" setting too dark except in a fairly dark room.
post #262 of 386
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.
post #263 of 386
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.
post #264 of 386
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.
post #265 of 386
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.
post #266 of 386
Quote:
Originally Posted by deadrody View Post

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.

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.
post #267 of 386
Thread Starter 
MagicPotatoes; A older thread, but a current issue.
That was a more extreme example of the problem. It probably should of been done 6 months (or more) earlier.

nivo885; Lamps have a break in period between 300 and 500 hours where the initial brightness will decrease and stabilize.
post #268 of 386
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...
post #269 of 386
The testimonials don't lie BadClams. Do it and you won't regret it.
post #270 of 386
Thread Starter 
But, if you don't feel confident, don't do it. It's not for everyone.

It's looking like between 1,000 & 2,000 hours seems to be the cleaning period. of course that depends on how 'dusty' your environment is. This is just a educated guess and also depends on how degraded a picture you will tolerate.
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