Screen is split horizontally

I have a Sony KDF-55XS955 rear-projection HDTV with a DirecTV RCA HD
box. When watching HD channels, I can see a very fine separation
running directly across the screen horizontally. It is very noticeble
when watching slow moving objects. It looks like a fine line separating
the top half of the screen from the bottom half. Others don't notice it
until I point it out. I do not notice the anomoly when watching regular
channels or DVD's and VHS tapes. I don't know if its because HD
channels are a lot sharper and more noticeable or it only has to do
with the way my TV and satellite box processes the HD signals. Does
anyone know what can cause this? Thanks.

On 1 Dec 2006 13:27:30 -0800, "rugrad9093"
wrote:

I have a Sony KDF-55XS955 rear-projection HDTV with a DirecTV RCA HD
box. When watching HD channels, I can see a very fine separation
running directly across the screen horizontally. It is very noticeble
when watching slow moving objects. It looks like a fine line separating
the top half of the screen from the bottom half. Others don't notice it
until I point it out. I do not notice the anomoly when watching regular
channels or DVD's and VHS tapes. I don't know if its because HD
channels are a lot sharper and more noticeable or it only has to do
with the way my TV and satellite box processes the HD signals. Does
anyone know what can cause this? Thanks.

I dont have the solutin but maybe a pointer in the right direction:
If the effect shows as a time delay between the two halves, it is
usually called "tearing". It is caused by an update of the frame
buffer in the middle of a read out.

Some reports this type of problem when connecting a PC to their TV
(that does image processing). In that case it is due to different or
unsynchronised frame frequency between the source and the display.
/Jan

Thanks, I'll look into that as a possibility. I've never heard of that
term before but you may be right. My problem is as though the screen is
split exactly in half and there's a slight horizontal shift between the
top portion and the bottom portion, thus causing the line to be
pronounce when you see slow motion on the screen.

Jan B wrote:
On 1 Dec 2006 13:27:30 -0800, "rugrad9093"
wrote:

I have a Sony KDF-55XS955 rear-projection HDTV with a DirecTV RCA HD
box. When watching HD channels, I can see a very fine separation
running directly across the screen horizontally. It is very noticeble
when watching slow moving objects. It looks like a fine line separating
the top half of the screen from the bottom half. Others don't notice it
until I point it out. I do not notice the anomoly when watching regular
channels or DVD's and VHS tapes. I don't know if its because HD
channels are a lot sharper and more noticeable or it only has to do
with the way my TV and satellite box processes the HD signals. Does
anyone know what can cause this? Thanks.

I dont have the solutin but maybe a pointer in the right direction:
If the effect shows as a time delay between the two halves, it is
usually called "tearing". It is caused by an update of the frame
buffer in the middle of a read out.

Some reports this type of problem when connecting a PC to their TV
(that does image processing). In that case it is due to different or
unsynchronised frame frequency between the source and the display.
/Jan