2011 Mitsubishi 3D DLP Owners Thread (740/840 series) - Page 111

i disagree. my 73840 appears to have deeper and inkier black levels than even my samsung pn64d8000 plasma which was measured at .006 mll. though the bias light behind the set has alot to do with that,im VERY impressed with the black levels on this set.

I think I'm going to call Mitsubishi today at lunch and see what they have to say about my geometry issue. Maybe I can get them to send out a technician to take a look. I really don't want to call Amazon again and have them do another exchange, especially since this seems to be a known issue with these TV's, I just don't know to what degree (is mine worse than normal, etc.).

My 92840 looks about the same as yours geometry wise. (I saw your pictures) I tweaked it as much as can be done. My screen bows in about 3/4". Pretty noticeable watching football last night with the lines on the field.
They're going to replace the screen. It'll probably be in next week.
I'd call a local authorized service place first. Describe the distortion the best you can. Pull a straight edge across to see how much it bows in. Measure your test pattern bars in the geometry settings to see how much they vary.
I had to also call Mits and get a case number. You'll be on hold for a while.
Also the screen only has a 30 day warranty. Don't know where you stand on that.
I hate being Mr. picky, but my other 4 Mits RPTV's were much better geometry wise.

I can't see how you guys managed to stay sane while waiting for your TV and accessories to arrive. I feel like shipping is via a kid and a little red wagon across the US. I'm trying to keep in mind that this will all be setup before the start of the NFL season, but I feel like Bill Murray in Groundhog Day waiting for the next day to come but it never does.

Is there a single place to find the remote code sequences for the various service menu options?

I have had this new TV for a week, so I'm good with the warranty. I was just trying to find other solutions if available before messing with Mitsubishi (and I too hate being Mr. Picky). Good idea about calling local authorized service centers. I am doing that now, to get an idea if they are knowledgeable about this issue.

I'm also going to have a friend come over this afternoon and let him push lightly on the inside of the screen (no, not with bare fingers) to see what that does to the geometry, just to do a little troubleshooting and make sure that the screen is the problem. I did it myself and it pushed out easily, and then retreated back to where it was when I released pressure, but I was not able to watch the screen while I did it. I'd have my wife do it, but she probably won't really even see it as an issue (she is not a visual perfectionist, like myself).

i dont know if this helps you guys,but i read this and thought of this thread and our geometry issues. taken from thx calibrator site lionav.com:

so it sounds like they can fix our geo problems AND provide us with a full thx/isf calibration. im seriously considering this unless someone chimes in with some better knowledge.

I've actually e-mailed Greg at Lion AV about this problem (they did my calibration for my old 65" Mits years ago), and after describing the issue, I asked him if it they could physically adjust the screen during a calibration, and he said no. He was also adamant about not doing manual geometry correction due to the loss of 1:1 pixel mapping (and he owns an 82740 which he loves). Now, I don't know if this means that the geometry can be corrected electronically without losing 1:1 pixel mapping (I didn't want to keep bothering him). I also talked with a local ISF calibrator, and he said that he didn't do physical screen adjustment, and I would probably want to talk to a calibrator who was also a service technician. There used to be one here in Atlanta (Mastertech), but I think he is retired as all the phone numbers seem to be changed and I e-mailed the one e-mail address I could find that seemed recent and didn't receive a reply. At this point, I want to get Mitsubishi involved.

I've had it suggested that I return the TV, but since I already returned the one to Amazon that had the 490 hours already on it, I've been kind of hesitant to do this. They were very good about the first one, but I feel like maybe I'm being picky on this issue since others seem to have it, and there is no guarantee that the next TV will be any better. Also, I just got notice today that they refunded $50 to my credit card for the first return, which I did not request, especially since I was able to watch the first TV (which didn't have any geometry issues I remember) up until they delivered the replacement. I'd rather Mitsubishi do the due diligence this time, I guess.
Edited by BrentBridge - 8/17/12 at 8:36am

well that sure is a bit of a letdown. the loss of 1:1 pixel mapping doesnt really affect me since i dont use my pc on my mits,but it would sure feel good to have correct geometry!

I hate to open a can of worms as I know this has been discussed, but is 1:1 pixel mapping more important wihen using a PC? From the discussions, I could never get a really good handle on it. I don't use a PC, just a blu-ray player and my HD cable box are connected to my TV. Truthfully, I cannot see a picture quality difference when I have used geometry correction and then when I have disabled it by pressing "1 - Enter" while in the "Manual Geometry Correction" screen. I can definitely see my corrections go away, but as far as the picture quality, it looks the same. Does 1:1 pixel mapping become more of an issue in certain circumstances?

Yes, as you indicated, 1:1 pixel mapping will make a difference when using the set as a PC monitor. Additionally, it is needed for 3D viewing, but these sets toggle that on automatically when in 3D mode. There is also talk that perhaps some can notice a difference in smooth motion vs. motion blur with anything other than 1:1 pixel mapping.

On that subject, I've never seen a DLP over 42" in which there are not at least some some concave geometry issues, regardless of manufacturer. I believe it is the nature of the beast.

I can contest to it being in my 61" RCA DLP also and with my many friends and family with their non-Mits DLPs. IMHO as long as it is close, it eventually gets "lost" in my mind over time.

I wonder if there is a way to "tighten up" the concavity of the screen by loosening the mounts a bit, pushing the screen out to flat position, and then re-tightening everything? Would certainly take some precision. I've called Mits, and they are setting up a service call with a local technician. I will see what he says I suppose. The Mits warranty/service guy said that the tech should be able to get the curving lines out with geometry correction. When I mentioned 1:1 pixel mapping being disabled, he pretty much said that it should not be noticable unless you were VERY critical and that this is how the units ship since they do geometry correction at the factory before shipping.

I did run a sting horizontally across my screen, taping it securely to the side of the bezel. Then, I gently touched the screen with a piece of paper and marked where the inside edge of the string was located, both at the edge of the screen and in the middle. The difference was 3/8". Not as much as g4s' screen was bowed from his post above, but still a substantial amount in my mind. I didn't move the string vertically up and down the screen to see if the bowing was different from top to bottom, but I might try that next.

I guess the next logical question is if the warped geometry can have any source but the concave screen... what about the big mirror on the back of the set that reflects the light to the screen?

EDIT:
Service tech coming out tomorrow, so I'll let you know how that goes.
Edited by BrentBridge - 8/17/12 at 1:26pm

I doubt it's a mirror problem. On my model the mirror has a bracket around the perimeter. If it was sagging in the middle I believe it would cause barrel distortion not pin cushion. The lines would bow in the opposite direction.

Keep in mind that the screen is natrually thin and flexible. It has to be simply to allow enough light to pass through. This flexiblity will prevent a perfect tightening of the screen. Also the screen must allow some expansion / contraction due to temperature changes that naturally happen. If the screen is too taught, this may be prevented. The way the screen is held in place may not allow alot of improvement. You may never get perfect.

I have notice the screen bezel of the 82" and 92" are of an entirely different construction so the way the screens are held in place inside these bezels for these larger sizes may be different than the 73".

I was just downstairs setting the geometry back to the factory restore setting in preparation for the technician visit tomorrow, when I noticed that there was ghosting around the geometry lines in the areas where they are curved, and there is no ghosting around the lines where they are straight. This makes me wonder if maybe the fresnel lens screen and the lenticular screen are further "separated" at the curved ghosting areas than in the areas where the lines are straight and without ghosting. Or, maybe the ghosting is just function of the bowing of the screen? But if this ghosting is present on the geometry screen I'm sure it is present in the picture when watching a movie. Anyone have any ideas?

I've been through three of the Mits TVs. The first was a 73840 that had a severe problem with a gap between the screen and the bezel that caused geometry issues. Also couldn't stand the SSE on the matte screen so I returned it and was able to upgrade to the 82840. The first one of those had an issue with the two screens being separated. That caused a blurring in the center of the screen which was especially noticeable when viewing text. Called Mits, they sent a tech out that said the screens had to be replaced so I had the whole thing replaced again since I didn't want a repaired TV. On the replacement 82840 I finally got the "WOW" factor and knew exactly what all the hype was about the clear contrast screen. Picture is awesome and much better than the matte screen IMHO.

You might try putting a menu guide or movie credits up then stand close to the screen and look down to see if the ghosting or double image appears. You want it right so do what you must to get it that way!!

Well, the technician has come and gone and nothing has changed. He tried to adjust the geometry manually, and pretty much got the same results I did. He said there was nothing wrong with the screen, that if the freznel and lenticular had separated then it would look a lot worse. Basically, he said that's just the way these tv's are.

I guess I'm going to call Mitsubishi warranty service again on Tuesday (after he submits his report) and see what they have to say. Looks like the only options I have are to live with it or get another replacement and hope that the replacement will be better. Getting a little frustrated with this TV. Anyone have any advice? Am I being too picky? Do I just need to live with some distortion at the bottom of the screen?

Yes, it seems you're being too picky. I would just enjoy the TV. How much can you notice the small linear distortion when you're watching movies and TV shows?

Am I right in that there are two input panels on the 840 series (rear and right side)? If so, then what are the inputs on both panels? I'm seeing conflicting information online.

There's one back panel on a 92840. Pretty sure other sizes are the same. http://www.mitsubishi-tv.com/asset/file/dim_sheet/dimsheet-WD-92840.pdf

If you zoom in on the picture (which is quite detailed in size), then you will see the second panel on the right side. It is also shown on photos online. (linked due to size for clarity when enlarged)

Not sure about the picture. I have a 92840 in front of me. There is a vent panel on the right side of the base. Looks like the power supply behind it.

Thank you. That was the conflicting thing I mentioned...some showed a panel and some showed a vent. I figured I should ask someone who had one in front of them. I am rewiring my room tonight and tomorrow to move everything around...92" and an entertainment system demands a lot of space. I am also doing my wire preplanning and now can move everything to one side and use push/pull fans for heat management, so you have been very helpful. Thank you again.

No problem. Sounds like fun. It's best to be ready when this monster shows up.

That's the plan thankfully for Newman's Own K-Cups. I'm so wired on caffeine, I may be done sooner than later.

The owner's manuals show the side connection panel (4th HDMI) on the 838 series, but not the 840 or 842 series. Older sets had the second jack panel in front, behind a door. It appears that they're reusing old photos in the ads.

Thanks for the info. I have cut half of my holes and installing the brackets. I had to stop for a delivery and install of my new Samsung Plasma for the MBR. I'm now waiting for my other cables and plates from Monoprice so I can fish them all at once. After becoming pissed today at the local prices for these items, I went ahead and rush ordered from MP and still came out much cheaper than local...amazing! Now back to Lowe's for primer (wifey is still pondering over color choices...had to let her feel a part of it all ).

Good to know, thanks for sharing. Still OLED and possibility other tech for LCD is on the way. I was speaking more in generalities and not model specifics from past to present.

ah,i see. im excited for oled,but next year i think ill go with the laservue. give oled a few years to work out the kinks