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View Full Version : Subtle backlight bleeding 46PFL6606H



ruudvdl
01-06-2012, 08:51 AM
Hi,

Yesterday I bought the 46PFL6606H. I installed it during the day and everything seemed perfectly fine.

However in the evening (with the lights on) I noticed a weird kind of backlight bleeding on the entire left and right edge of the screen (not just in the corners). It's not simply "light bleeding through", but it's more like a vertical bar (4 cm wide) in which brightness is higher.

That means if the left or right are completely black, the areas are not affected. Also if the picture is completely white, it is not visible. However, on the grey Philips startup screen directly after turning on the tv I can see that the left and right are brighter.

I upgraded to the latest firmware but I did not see any improvement (it does play 24p without judder now though, which was a problem before).

My settings:
- all image enhancements off (except clear lcd; that one's turned on)
- brightness 51
- contrast 54
- gamma 0
- red/green/blue: 104/84/42

Turning on dynamic contrast improves the problem (best results at maximum), but it's still visible. Is my panel defective (sure looks like it, even though only greys are affected), or is this a firmware problem?

Can anybody with the same tv check if they notice the same problem? It is very visible in a dark room when turning on the tv on the Philips logo (the black-on-grey logo directly after turning it on).

zlatko
01-06-2012, 09:30 AM
@ruudvdl
have a look at this thread: http://www.supportforum.philips.com/en/showthread.php?3760-Your-experiences-with-FW-v0.14.93.0-for-8000-9000-and-21-9-series-(2011-models)&p=22386&posted=1#post22386

Looks like a similar issue, but with direct LED screens. Still no official Philips statement.

ruudvdl
01-06-2012, 09:41 AM
Yeah, sounds like the same problem. The effect is very subtle but nevertheless annoying.

When I first noticed it it felt to me like it was a software problem: why else would it not occur on completely black or white pictures? Local dimming has almost no effect on my tv by the way. I'm wondering if local dimming is still used even if it's turned off, and a software glitch calculates too much brightness near the left/right edge in some cases.

ruudvdl
01-07-2012, 12:43 PM
The problem is much more visible when I open the menu of my Onkyo receiver; the backlight bleeds through both sides of the screen. You cannot miss it.

A video demonstrating the problem:
http://www.youtube.com/watch?v=6uqgfulqYCM

Maybe a Philips engineer can respond to this and check out the video? Is this a monday morning model or might it be some kind of firmware bug after all? Plus, what is the preferred way of returning the tv?

TechnicsKuzya
01-09-2012, 06:13 PM
Same problem - only PC mode fully disable Dynamic Contrast (or something other processing)

http://www.supportforum.philips.com/en/showthread.php?3772-Your-experiences-with-FW-v0.14.93.0-for-5806-6000-and-7000-series-(2011-models)&p=22672&viewfull=1#post22672

ruudvdl
01-09-2012, 06:59 PM
@TechnicsKuzya: so if you turn on PC mode the problem disappears on your tv? (no more edge bleeding on PC mode?)

I won't be home until tomorrow. I'll try it as soon as possible then.

TechnicsKuzya
01-09-2012, 07:42 PM
Yes, try enable PC mode and disable Optical Sensor, but I'm liked Natural Motion - in PC mode, it`s don`t work... :(

ruudvdl
01-10-2012, 07:36 PM
Turning on PC mode + turning off Optical Sensor doesn't seem to change a lot. The extreme effect I had when I opened the onscreen menu does seem to be gone now though, there's just the subtle effect I mentioned before.

During the day when the screen is brighter the problem is almost invisible. I had a lot of trouble checking the problem during the day, but during the evening the problem is clearly visible (regardless of optical sensor being on or off).

Hope it's not a software problem. I'll call the Philips helpdesk tomorrow.

Philips - Thomas
01-27-2012, 03:58 PM
Hi

the behavior is normal and related to the Dynamic Contrast.
Only way to minimize this is to diesable Dynamic Contrast.
BUT
It is not possible to have this completely changed!

Regards
Thomas

ruudvdl
01-27-2012, 04:02 PM
Hi Thomas,

Dynamic Contrast is turned off already (set to off); I double-checked this! Also I think the amount of bleeding in the youtube video is too extreme to be called normal. The video was recorded with my phone; in reality it's more visible and perhaps less subtle than I described.

The problem is very visible in the dark-gray PHILIPS startup screen (especially the bottom right which is worse than the rest), so I think it's a hardware defect or a monday morning moel. I'm currently trying to contact the store and will try to exchange it for a new screen. :)

Regards,
Ruud

zlatko
01-27-2012, 05:30 PM
@Thomas
My regards Thomas, but that can NOT be called "normal". You can say it is unavoidable defect/consequence of Dynamic Contrast and I will be fine, but calling it "normal" is absurd.
So you are stating officially that Philips will not even put some effort in correcting it?
Also I notice it on direct LED 52PFL9606(although rarely and more subtle, than what I see in ruudvdl's video) which is different kind of screen with individually controlled LED zones.

ruudvdl
01-27-2012, 05:38 PM
@zlatko: I think my screen is defective.

If you put up a dark gray picture and stand close to the tv, you can see a 'black circle' which is an lcd polarisation effect; the center is the darkest because you watch it from a 0 degree angle. The closer you get to the screen the smaller this circle will get (because of the increased angle between your eyes and the rest of the screen).

This circle just stops at the left and right edge of the screen; it seems like the top layer of the screen is bent there (which can also be seen if you look at the bezel standing very close to the screen; it looks as if the top layer of the screen is folded inside).

This looks like it's a production error of some sort. I'm in the process of swapping the screen and I'll report back soon. Looks like your and my problem may be unrelated. In some movies the effect is very prominent and pretty extreme (not so subtle, regardless of the topic name I entered earlier). Also it is very noticable at the gray philips startup screen, or if I use my pc to produce a full dark gray picture (like RGB 20,20,20). The edges are almost 50% brighter then. Hope your problem isn't this bad!

zlatko
01-27-2012, 05:47 PM
@ruudvdl
I rarely notice it on my TV, and I even can not call it annoyig or distracting in any way. Nothing near as unpleasant as the famous now Philips DirtyScreenEffect(DSE).
I was just shocked that official Philips rep here can state that what is seen on your video is "normal". From your last post I get your screen itself might faulty, so that I hope will be an easy swap. Wish you smooth exchange and many happy hours watching the new TV set you will get!

ruudvdl
01-27-2012, 05:53 PM
Ok, thanks. I'll report back here after the swap is completed!

Piddmaister
03-21-2012, 08:44 AM
Hi guys,

I got my 46pfl6806t yesterday and I have the same problem with the bleeding edges. During the days I canīt see it but when it gets dark outside they appear. I noticed that if I mess around with my settings I can lower the effect but itīs still there. I have calibrated my settings based on this article http://www.flatpanelshd.com/review.php?subaction=showfull&id=1312271877 and then fine tuned what I think look good.

I havenīt tried updating the firmware yet, will look into this tonight.