s video vs composite on DBS (1 Viewer)

[Greg Kolinski]

A while back I read a post about s video hookup vs composite on DBS hookup.Basically it delt with the possibility that better PQ can be had using composite due the the better comb filter in the TV than the DBS reciever.I have my stuff hooked up both ways,and just really cant tell a difference.Anyone else messed around with this?

thanks
Greg Kolinski

 

[Philip Hamm]

There's no comb filter in the DBS box. Digital Satellite is broadcast as seperate chrominance (sp?) and luminance. It makes no sense to use composite if your TV has an S-Video input.

 

[Eric Stuckey]

Same thing here. I just upgraded my DSS last weekend and hooked it up with composite and there's about a 20-30% improvement. I have a New Hitichi HDTV that has 1080i.:b

 

[Allan Jayne]

Some digital satellite systems include some analog source channels that do not have luminance and chrominance separated prior to transmission. Your satellite tuner box needs a comb filter to make good S-video from them. Some tuner boxes use a filter similar to that in a cheap composite to S-video converter rather than a comb filter. Here you might find that composite to the TV looks better.

Video hints:
http://members.aol.com/ajaynejr/video.htm

 

[AaronBatiuk]

Some digital satellite systems include some analog source channels that do not have luminance and chrominance separated prior to transmission

That is not true. Although many digital satellite channels come from analog sources rather than directly digital, they too are digitised and transmitted in MPEG-2. The luminance and chrominance components need to be digitised seperately, so a comb filter is required beforehand (and the end user has no control over the quality of this filter or the artifacts it introduces, unfortunately). MPEG-2 also does require seperate luminance and chrominance components (YUV in digital).

Now, the story for digital cable boxes (which do qualify as DBS - Digital Broadcast System) is entirely different. Here, you have analog channels in addition to digital channels. All of the analog channels need to be separated into Y/C if you use the S-Video connection on the cable box to the TV. I can't imagine that the Y/C filter in the cable box is nearly as good as the one in the TV, which for a good modern TV is probably a digital or multi-tap comb filter, which yeilds excellent results.