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I've recently purchased a Panny plasma. I have Comcast analog cable and have the cable hooked directly to the TV. I am able to receive HD channels from OTA broadcasters. I believe this is refered to as Qam or clear Qam. What perplexes me is that a couple of local channels (this is from the Boston area, WLVI and WSBK) the HD channel is shown in the AR of 4:3 but the analog channel is shown as 16:9 for the same program. This confuses me because doesn't the HDTV specs call for 16:9? So I wondering are these programs being shot at 4:3 or 16:9?
 

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Quote:
Originally Posted by ftran999 /forum/post/15418369


I've recently purchased a Panny plasma. I have Comcast analog cable and have the cable hooked directly to the TV. I am able to receive HD channels from OTA broadcasters. I believe this is refered to as Qam or clear Qam. What perplexes me is that a couple of local channels (this is from the Boston area, WLVI and WSBK) the HD channel is shown in the AR of 4:3 but the analog channel is shown as 16:9 for the same program. This confuses me because doesn't the HDTV specs call for 16:9? So I wondering are these programs being shot at 4:3 or 16:9?

Your TV is probably stretching the 4:3 content. When you tune to a HD channel, the transmission is actually in a 16:9 format. However, if the material is only 4:3, the rest of the frame is filled with black bars. The actual resolution coming to your TV is 720p or 1080i.
 

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The specific content you referred to is being provided to your station in 4:3 on both your analog and digital. The difference is what the previous reply explained. If you were to set your TV's view mode to "Normal", or whatever term your TV uses for normal, then the analog would have the same overall look as your digital with that specific content (content in the middle, black boxes on the side).


Now, if you were to switch between the 2 during an HD presentation, then things would look different. Depending on the network your analog picture would either be cropped or presented with the black boxes on the top and bottom.
 

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Quote:
Originally Posted by machpost /forum/post/15418923


Yep, if I'm not mistaken, this is the default setting for Panasonic plasma sets, out of the box.

It seems to be the default for most TVs out of the box. I've had experience with my Pioneer HDTV. It was set out of the box to "WIDE"=which is a hideous Turner/TNT-style non-linear stretch. It looked like a funhouse mirror. This was to someone who hadn't seen an OAR picture on an HDTV before. That bad.



The other was an Insignia 19 inch TV I set up for a friend of my mom. This one was also set to stretch, which I corrected and explained why the bars were supposed to be on the sides.


You need to use your TV remote to set the TV to 4:3 on SD channels. Usually there's a button: Screen Size, Picture Size, Aspect Ratio or the "#" button on Scientific Atlanta remotes. This will set SD content to 4:3 as well. The HD channels are coming through in 4:3 with bars because the sidebars attached are part of the content from the source. Unless an affiliate pre-stretches their broadcast, the broadcast goes out with bars on the side.
 

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Ftran,

All OTA digitasl channels do not broadcast in 1080i or 720p HD resolutiions. Many mostly the PBS channels still broadcast only in SD 480i.

The network affiliates will broadcast the primary (-1 or .1) channel in HD resollution and their other sub channels -2, -3 etc in SD.

OTA digital channels use 8VSB transmission protocol, QAM or clear QAM trasnmission protocol is only used by cable channels

Digital channels can be either SD or HD. However, all HD channels are digital.

Also not all programs shown on HD resollution channels have HD content since many are still filmed with SD cameras. When a program filmed with an SD camera is shown on a widesceen HD channel black/grey side pillers are added to the video content in order to the change the aspect ratio from 4:3 to 16:9.

And as pointed out by the above posters it appears that your Picture size settings on your TV are not set correctly for each of the resolutions you are receiving.
 
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