# HDTV Settings on ViP622 - 720P or 1080i?



## cmilviper (Mar 7, 2007)

Hello all,

I have a 46 in. 1080P Samsung LCD. 

On the HDTV settings on the ViP622, should I have it set to 720p or 1080i?

I watch a lot of ESPN HD, Discovery HD, HBO HD, as well as the local HD channel content.

Thanks for the help and explanation.

CMilViper


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## Rob Glasser (Feb 22, 2005)

Welcome to DBSTalk cmilviper.

As for your question, it's kind of a loaded question. Really it's up to you as to which one looks better. Typically you want to try and match or as closely match the native resolution of your TV. For a 1080p TV you're probably best off with it set to 1080i. If I were you I would spend some time watching TV at both settings and see which you prefer.


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## cmilviper (Mar 7, 2007)

Thanks Rob, I appreciate it!


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## Mr.72 (Feb 2, 2007)

IMHO ... progressive scan & 60 Hz frame rate trumps resolution every time. Pick whatever looks best, but for sports in particular, I'd expect that to be 720p. You're losing half the frames if you go with 1080i and watch ESPN-HD.


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## edknarf (May 23, 2006)

I have a Samsung LN-3241D, that can display 720p and 1080i. I know the ViP622 gives the option of outputing in either 720p or 1080i. I have it currently set to output in 1080. Is there any advantage is switching output to 720p for an HD program that was orignally displayed in 720p? Thanks.


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## Mr.72 (Feb 2, 2007)

Yes there is an advantage. 1080i is 30 frames per second, 720p is 60 frames per second. If you "convert" a 720p stream to 1080i, not only do you get the scaling artifacts, but you also lose 1/2 of the frame rate. Every other frame gets deleted.


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## Stewart Vernon (Jan 7, 2005)

For the record... I have never seen anyone say for 100% certainty that the 60 frames per second in 720p are all unique frames. Speculation has said that at least some channels using 720p at 60 fps are actually using 30 fps master with each frame sent twice.

In that situation, throwing away every other frame would not be losing any new data after all in the conversion to 1080i... so it would only be the conversion process of manufacturing data that you would potentially see.


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## podder320 (Mar 4, 2007)

cmilviper said:


> I have a 46 in. 1080P Samsung LCD.
> 
> On the HDTV settings on the ViP622, should I have it set to 720p or 1080i?
> 
> I watch a lot of ESPN HD, Discovery HD, HBO HD, as well as the local HD channel content.


I want to add two things to the suggestions already presented.

First, there are some HD channels with 1080-size material, so using 720p will lose detail and sharpness when watching those. Searching this forum turns up multiple lists of which channels are sourced at what resolution, and the 622 won't tell you. CBS HD is usually 1080i but it might depend on your local; ESPN is 720p.

Second, you might want to look at my thread here about non-HD image quality problems in the 622 at 1080i: if your 622 exhibits the behavior I'm seeing, then standard def channels will look better with the 622 putting out 720p.


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## TorinoCobra (Sep 24, 2006)

I have a Sony KDL-46XBR2 1080P LCD. I originally had my 622 set to 720p, but noticed that I was losing portions of the picture to overscan. The Sony will do full-pixel (no overscan) but only for a 1080(i or p) input. I switched the 622 to 1080i, and set the Sony to full pixel. I now get the complete picture, and for most source material, a perfect picture. Some signals, however, display a small band of "digital noise" at the top. It's annoying, but I can live with it. YMMV

Gregg


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## jcrobso (Mar 30, 2005)

HDMe said:


> For the record... I have never seen anyone say for 100% certainty that the 60 frames per second in 720p are all unique frames. Speculation has said that at least some channels using 720p at 60 fps are actually using 30 fps master with each frame sent twice.
> 
> In that situation, throwing away every other frame would not be losing any new data after all in the conversion to 1080i... so it would only be the conversion process of manufacturing data that you would potentially see.


Just some FYI: Per the ATSC standard 720p can be at 60fps, 30fps or 24fps!!!!
How to tell which one you are watching,,, beats me. When I go to the NAB show next month I'm asking some questions. John


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## Mr.72 (Feb 2, 2007)

However, you should note that the output of the 622 is not ATSC native-pass-thru, and even if it was native-pass-thru, the encoding on the head-end is not necessarily ATSC copy of the source material.

According to my TV ... 720p out of the 622 is at 60 Hz. The incoming data stream may very well be 24fps all the time and cadenced to 60 by the 622. ATSC standards are sort of irrelevant unless you are talking about an OTA broadcast, other than simply finding some format that will sync with the TV.


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