My new Panasonic TX-37LZ800

Forums › Home Theatre (including HTPC and EPG Collector) › My new Panasonic TX-37LZ800 - A problem?

nzgadgetman

43 posts

Geek

#25261 16-Aug-2008 21:58

Hi Guys,

Basically just after advice - I've not paid much attention to LCD TVs in the past, but have been around LCD monitors a lot and I've not had this problem very often...

The issue is that when there is a dark image, the backlighting is noticable patchy. During normal daytime TV this isn't a problem but at night in a low-lit room, when watching a program with dark scenes (surprising how many of these there are!) it is *very* obvious.

To show you what I mean I've selected an un-used input - the TV displays a black screen, and I took a photo of this "black" screen.

Now I know that the black quality of an LCD isn't as good as a Plasma, so I don't need to be told about that :) Buuuut, I did expect it to be of even brightness (the same as my LCD projector).

So the question - based on the photo above, do I contact the retailer (Harvey Norman) or Panasonic and ask them to do something about it, or is this normal for LCD TVs?

Cheers,
Ben.

AncestralGeek

91 posts

Master Geek

Lifetime subscriber

#157469 16-Aug-2008 22:45

Hi Ben

I also have a TX-37LZ800 which I am very pleased with. Saw your post so turned out all the lights and switched over to a unused channel. Just blacknes. Went into the setting menu and cranked the brightness up to 100% and contrast 100%. Display is now visible but very even, not perfect but very OK.

Two things you coud try. Set contrast to 80% and brightness to 50% and see if that helps. Also somewhere there is a setting refered to as "Shop Display" setting?? which may be selected rather than the "Home" setting which it needs to be on.

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nzgadgetman

43 posts

Geek

#157470 16-Aug-2008 22:48

Thanks for the reply. The brightness is set to 50, contrast @ 90 (default), though it seems to make little to no difference what these are set to. It is set to Home, not Shop Display.

A point I should make is that I used a long exposure to capture the extent of the blotchyness, so the whole thing in reality is quite a bit darker, but the blotches from the corners are annoyingly noticible.

So I guess I go in to Harvey's tomorrow and have a chat!

RicardoX

3 posts

Wannabe Geek

#158141 19-Aug-2008 21:06

"So I guess I go in to Harvey's tomorrow and have a chat! "

How did you get on with Harvey Norman NZGadgetMan? Were they willing to play ball and give you a replacement?

Funnily enough I just got a 37LZ800 and think it is great (way better than my gen 2 Sony LCD) aside from I have the same issue with the backlight bleed effect. Only really annoys me on dark scenes but still there and shouldn't be.

I emailed Panasonic NZ Customer care and they said they hadn't heard of that, so were surprised by the problem and advised to take it back to the store for a replacement (JB HiFi), so off to return it on the weekend.

Keen to hear if a replacement cured this problem for you and all is happy again in Panny-land.

Cheers.
Rich.

nzgadgetman

43 posts

Geek

#158149 19-Aug-2008 21:25

Indeed I did go in for my chat. They were very keen to put it right, and were all happy to replace it then and there.... until they checked and had no stock!

We then proceeded to discuss other options, but all I was really interested in was the 42PY800 or the new Samsung series 6 40". The PY800 they wanted another $700 for (wife approval denied) and the Samsung is end of September or October!

So the end result was I'm waiting for another LZ800. They're letting me keep the current one until the replacement arrives so that's good. As I said from the beginning, I'm happy with the TV, and I like the brand, just not happy about the backlight!

New one due in on the 30th, so will post back here with the end result!

Cheers,
Ben.

RicardoX

3 posts

Wannabe Geek

#162318 4-Sep-2008 22:09

Funny story - my corner bleeding has gone away before I got a chance to take it back. Basically I had a bit of a prod around where the bleeding was and it appears the outside casing was not quite fitting right - a couple of clicks in to place and everything seemed to come right. There is still a minor amount of backlight visible, but it is uniform now and "normal" for an LCD (still better than my last Sony and overall picture way better). That said would be nice if I could turn the backlight down to little eliminate it (actually despite what I said about the old Sony, it did have this feature which was useful). Anyway, I figured the miss-fitting case was putting pressure on the screen causing the "bleeding" and once the pressure had gone, things came back to normal. Wonder if this is a common problem...

The desire to turn down the backlight altogether lead me to another discovery I made about the TX-37LZ800 / TX-37LZD800 while mucking around. I was trying to get in to the service menu, to turn the backlight down, based on other similar panasonics methods I've seen posted, and I found the following:

Hotel Mode Menu

Hold "Vol-" on TV and press the "AV" button on the remote 3 times (use exit via on screen menu to exit)

This seems to give you the option to turn the Hotel Mode on and a few related options to set when in hotel mode.

Test Patterns

Hold "Vol-" on TV and press the "Option" button on the remote 3 Times (Had to turn off on TV to exit)

Seems to put the TV through its paces with various colours and test patterns being displayed

Self Check

Hold "Vol-" on TV and press the "OK" **OR** "Menu" button on the remote (both seems to access the same Self Check function). Had to turn the TV off to exit.

It’s called the self check but pretty much just displays information about the TV

Service Menu

Hold "Vol-" on TV and press the "Recall" button on the remote 3 Times (Recall is to the left of 0, the symbol looks like a TV shaped rectangle with a cross in the bottom corner) (Exit button exited)

You then get various (service looking) menus to cycle through. Push 1 or 2 to cycle through top level menus and then 3 or 4 for the sub menu of each top level - a little hard to follow at first but makes sense once you've done it a couple of times. If a sub menu has a special option the key access method is displayed on screen.

Through the service menu I was able to adjust the Backlight (Or BACKLGT as it was called in the menu - hope this was the right one!) from 546 down to 4C6 (it’s a hex number) - range seems to be 000 to 999 (again, in hex) but I got bored so only got down to 200 and up to 800. I haven't experimented too much, so no idea if my new setting is the best, just took a guess and will take the time to tune properly in the weekend.

So hope this is useful, but obviously (everyone) use this stuff at your own risk. I'm no TV engineer so don't know the official process, this is just my findings from playing that I thought I'd share (read: All care, no responsibility!)

Cheers

Richard

RicardoX

3 posts

Wannabe Geek

#162325 4-Sep-2008 22:19

Oops typo on last post.

For Service Menu: "Hold "Vol-" on TV and press the "Recall" button on the remote 3 Times"

should read "Hold "Vol-" on TV and press the "Recall" button on the remote 6 Times".

So a few more button presses required unfortunately...