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NTL, Football etc on LG plasma

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strackal

Guest
Hi ppl,

I have recently bough the LG 42" plasma and have it connected to my NTL digital via scart.

The thing is, when watching for example, live footy the screen seems very blurry and shadowy when the players are whizzing about !?

Im going to upgarde to a monster gold plated scart, see if it makes any diff ..has anyone else experienced this?

Is this a quirk with plasmas??

anyone else got NTL box attached to a plasma?

Cheers for any advice!
 

eddiewww

Active Member
we ALL have it m8 !!!!

this is copied from here..

http://www.avsforumfaq.com/~plasma/#arti

Video artifact are generally divided into several categories:

1. Deinterlacing artifacts

NTSC and PAL (Standard Definition TV standards) are both interlaced. That means that they divide the image into two halves - the even rows are sent separately from the odd rows. Each set is called a field. A frame is composed of two fields. PAL transmits fields at 50 Hz (50 times a second), while NTSC transmits them at 60 times a second (60Hz). This was required in order for the older CRT Television tubes that were available in the 1940s, when television technology was first implemented. Sadly, not much progress has been made in this field and this is still the predominant method of transmitting and receiving television signals. Plasmas (and other digital display devices) display the entire frame at the same time. This is called a "progressive display".

In converting from interlaced to progressive, there are many different techniques which range in price and complexity. There are two primary types of conversion: film and video. Film mode depends on the fact that the original source was derived from 24fps film, processing usually converts such material using 3:2 inverse telecine (usually known as 3:2 pulldown) for NTSC and 2:2 pulldown for PAL. Video relies on the fact that the original source came from a video camera. Simple video techniques (Bob/weave) basically try to force the two fields into one frame. More complex (and expensive) techniques involve motion adaptive and motion corrective algorithms for deinterlacing (converting an interlaced source into a progressive output).

Unfortunately, each technique has its pros and cons. The cons are deinterlacing artifacts. These include zipper (horizontal lines towards edges of moving objects), jitter (thin vertical lines that either disappear every half a frame, or move up and down very quickly), jaggies/stairstepping (jagged edges of objects that should look smooth).

2. Scaling.

Once a signal is deinterlaced it is usually scaled (see: Native resolution) to try and fit the Plasma's native resolution (if it doesn't, the internal scaler within the plasma should adjust and rescale to native resolution). There are many methods to upscale signals. However, not all of them perform equally. The original "scaling" method of duplicating scan lines (hence the term: line doubler) kind of works ok for some projectors, however it will cause pixels on the plasma to appear twice as long (i.e., hideous). There are many scaling engines out there (of particular note is the Radeon engine by ATI which is one of the best hardware scaling engines built so far). Bicubic scaling is considered to be the typical method for accomplishing scaling without adding artifacts like pixel stretching.

3. Motion.

Motion artifacts are artifacts that appear when objects are in motion. This is usually due to deinterlacing artifacts in algorithms that cannot cope with motion. When algorithms can't cope with motion, they usually drop to bob/weave (either for the entire frame or for a specific section of it where they can't determine what's going on). That means a loss of resolution, and various different types of artifacts.

so i want to try 2 things...

http://www.av-sales.com/plasma/html/brite_view.html
or
http://www.av-sales.com/plasma/html/prov_converter.html

i need to know if anybody has tried before i splash out.... i may have to bite the bullet !
 
S

strackal

Guest
is this prov unit the solution? or will i still get problems?

I have a tv tuner box that came with the plasma, is that the same as this prov?

..soz im a bit of a newbie :)
 

eddiewww

Active Member
no... both the units take the signal and de-interlace before outputting a progresive output...

i am going to hang out in the progressive area and see if i get any more info....
 
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strackal

Guest
im getting confused now ....

Is there a solution?

whats the progressive area??
 
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davejw

Guest
Check the strength of the synch signal out of the NTL box. Are you using the RGBS output? into which input on your plasma?

Dave

PS look at the bottom of the main forum page techhie things the prog scan forum is there.
 
S

strackal

Guest
im using rgb output from the ntl box. howd do u check the signal from the ntl box?

could a weak signal cause this?

would upgrading the ntl coax connection be worthwhile?
 
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davejw

Guest
Check the info on the plasma it will tell you what it sees as the incoming horizontal and vertical resolution. Sometimes the composite synch signal is weak from devices I have had this issue with the NTL/Telewest Pace models. If so try a synchblaster cable or one of the RGB to VGA converters from JS Tech. To use a high cost scaler is expensive and then you start to see other Plasma shortcomings compared with LCD / CRT / DLP techmologies. However for day to day viewing superb.

Dave
 

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