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General discussion

Color bleeding

Feb 16, 2009 11:31PM PST

I have noticed some color bleeding on my new PN50A530. Colors displayed on a white or light background bleed a bit to the left (no vertical bleeding). If there is a 1-800 number displayed in yellow on a white background, you see a whole yellowish bar covering the number. White text displayed on a black background has crisp edges, no bleeding. I don't notice the bleeding much at all during regular tv watching, but during advertisements it is more clear when they have text on the screen. There is also some ghosting, also noticeable only with small text, to the right of the text.

Anyone have similar problem? Can anything be done about this?

It doesn't seem to related to tv settings. You can lower the contrast to 50 and still see the same thing. Other setting changes I have tried also don't seem to affect this, but I could be missing something.

Discussion is locked

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HD or SD?
Feb 20, 2009 3:48PM PST

newhd,

Are you watching high definition or standard definition signals when you see this occur?

--HDTech

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Re: HD ord SD
Feb 22, 2009 2:25AM PST

This is in SD. Don't have HD box or a blueray/upconverting dvd player yet. Should this make a difference?

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SD bleeding?
Feb 24, 2009 6:23AM PST

Any ideas? Can color bleeding occur simply because the signal is SD?

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Noticed simmiler affect.
Feb 24, 2009 11:38AM PST

I noticed something similar on my LCD LN32A550. I have not started troubleshooting my problem yet, so I will be interested to see what people say about your problem. I am using a DirecTV HD receiver, and I noticed it when there were some thin white lines going horizontally across the screen. It looked the same as when the convergence is off on older CRTs. Since it is an LCD, this should be impossible. I do not see the same problem now while using it as my computer monitor, so I do not think my TV is at fault.

How do you have your source hooked up? Since it is an SD signal, is it a cable or satellite box? Make sure you are using the best possible connection your box supports. I would use S-Video or component cables if your box supports it. If you are using the old composite (single RCA for video), or, you are using a coax from a "TV out" and tuning in to Ch 3, your picture quality will be far from the best your TV can give you.

Also, look at the quality of your cables. If the shielding is week, or if there is a slight short between the shielding and the conductor, or cable quality is poor (thin), you will see image quality problems.

The ghosting problem sounds a little like what you can get from analog over the air reception when you get multi-path reception from the station (eg, signal straight from the TV station, and then the same signal after it has bounced off a wall, mountain, etc, causing it to be received slightly later it time). If you are using cable, this could be their fault as they might be using an antenna themselves to pickup the signal.

* First thing I would do is hook up an antenna to the back of your TV and watch some OTA HD channels. I pickup much more HD channels then I could with my old SD TV. This will allow you to see what your TV can do in HD, and will rule out any problems caused your cable or satellite company.

* Second, make sure you are using the best possible output to your TV. HDMI is the best, Component next (3 RCA cables for video), then S-Video, then composite (single RCA cable), then last is coax.

* Try different cables to make sure you don't have a bad cable.

* See if there is a firmware update that addresses your problem. Just be careful with firmware updates and follow the directions to the letter as firmware updates can go very bad. Just look around at this website and you will find a few examples.

Also, one of the draw backs of a good HD TV, is that it will show any and all defects in your source signal. Most, if not all cable and satellite companies compress the video signal to squeeze more channels through. When I had Comcast, the digital artifacts caused by their compression was so bad, that I got canceled it. (and that was when I had an old CRT ST TV). Also, I have never seen SD look good on an HD tv. So, when you get HD, you should notice a world of difference


Good luck! If I track down the cause of my "convergence" problem, I will post it here to see if it applies.

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will change cables
Feb 25, 2009 6:04AM PST

Thanks for the helpful suggestions. I have a Directv SD receiver hooked up to the tv by a coax. I will change that to component to see if it makes any difference. I did try a different coax cable but that did not have any effect. I have updated the firmware to the latest version. I am not sure about the reason for ghosting, because the reception is through the directv dish.

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Bleeding...
Feb 25, 2009 3:27PM PST

Well, Standard Definition inputs have 480 lines of resolution. The panel in question has 1080 lines of resolution. So while the television's processor will always upconvert it, it has to add picture where none exists.

Think of SD signals as zooming in a little close on a small picture file on your computer.

This "guessing" isn't always an exact science, and can cause some fuzziness or color inaccuracies. If you add any measure of static, then it can start to distort the picture. If I'm imagining your description correctly, that may seem to be the case. I do believe with an HD signal, that issue would be more than likely non-existant.

But keep me posted. I am watching this thread.

--HDTech

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Woo hoo!
Mar 2, 2009 11:53PM PST

Ok - I think the problem is solved. First, as suggested by The_Pickle, I changed the connection between (sd) STB and the tv from coax to s-video. The ghosting is gone, and the bleeding is minimized very much!

Secondly, also as suggested The_Pickle, I got a rabbit years antenna to try and pick up an hd channel. Bada boom, what a great picture! I haven't noticed any bleeding or any PQ problems at all. Unbelivable. I would have never thought of buying an antenna from the 50's to get a hd picture on the latest and greatest equipment.

Coax can carry multiple digital channels from your dish to the STB. Coax can carry hd channels from your $10 antenna to your tv. But it cannot carry one hd channel from your (hd) STB to your tv, and won't even properly carry a sd channel from a (sd) STB to the tv. Confusing for sure, but looks like that's they way it is.

Thanks to Samsung_HD_Tech and The_Pickle for all the help!

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Glad to here your problem is solved!
Mar 3, 2009 11:47AM PST

I think the poor picture quality you had with the coax cable is likely your DirecTV box.

When you connect the STB to your TV using a s-video cable, the video signal is transmitted to your tv as a video signal. When you use a coax cable, the STB has to convert the video signal into a "radio frequency" signal (a process called RF modulation) that would simulate what a TV would receive over the air. My guess is the RF modulator in the direcTV STB is cheap. Your older TV probably showed the same flaws, but, you just didn't notice them as much. Where your new TV's higher resolution, these flaws became more apparent.

One way to prove this is to tune into an analog channel (if they are still broadcasting where you live) and see what the picture looks like. My guess is that your picture will look better then what you saw on your STB using a coax cable, but nowhere near the picture you are getting on the HD channels!

If you plan to stay with DirecTV, you will have to upgrade to High Definition if you want to make your new TV shine. When you upgrade to HD (DirecTV, Cable, etc) make sure you connect your HD STB to your TV using a HDMI cable. The signal going through an HDMI cable are digital, so your TV will be showing the exact picture your HD STB is receiving.

Also, don't confuse digital tv with high definition. Your standard definition DirecTV box is receiving a digital signal, but, the source signal is still a standard definition image. To get high definition with DirecTV, you have to get a new box from them that is able to receive their HD channels. Both the HD and SD channels are received digitally, but, the difference is the source. A HD channel is 1920x1080 or 1280x720 where your SD channels are 640x480. With about 4 times as many "pixels", you can see why HD will always look better then SD. (think of receiving a low resolution picture vs. a high resolution picture by email. Both pictures a "digital" file, but one going to look much better.)

When you get a blu-ray, or an HD STB, make sure to connect it to your TV using an HDMI cable! Without it, you will most likely be watching SD again!

Glad I could help (and hope I didn't just confuse you more....)