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Old 01-18-2013, 07:27 AM
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cwsqbm cwsqbm is offline
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Originally Posted by MatWiz View Post
This is a very well known fact, OTA, antenna has the FULL, HD. You can not get better quality than the Of The Air broadcast of the TV station.
Well known facts are often wrong, misleading, or not the entire story. For example, blu-ray has the potential to have better quality than OTA. For movies, usually so since the original version for the theaters has to be recoded to a lower bit rate for blu-ray or OTA. With recent TV shows, not usually as they'd rather fit more episodes per disc than go back and recode the original video to a higher bit rate than what was first broadcast, and the broadcast quality was pretty good in the first place.

Originally Posted by khovik View Post
Not all full HD is created equal. The distribution networks often distribute the different channels at different bit rates depending on their popularity (esp. on cable or OTA where bandwidth is limited).
Yes, but bandwidth is limited everywhere, not just cable and OTA.

Originally Posted by MatWiz View Post
You are getting a "pass through". (you could probably set up your cable box for a pass through too). But it is not the same as the OTA quality.
To be more accurate, you should have said "its not necessarily the same quality as the OTA transmission." In my case (and there are other examples out there on the internet), the video I receive over cable via Clear QAM is the same quality as the OTA video. The actual QAM signal takes up about 1/2 the bandwidth of OTA because it lacks the error correction (which isn't needed with a good physical connection). The final video is the same bit rate and resolution and the same encoding method and therefore, the same quality.

Originally Posted by MatWiz View Post
They just can't send you all the digital information of the original 1080i or 720p, of all the stations at the same time over a cable.
Actually, they can. There's not that many OTA channels, and you can shove a lot data through a coax cable. The issue comes with all the other channels, but that's handled with channel switching. Within a given area, only the channels being asked for by cable boxes in that area are sent. There maybe 500 houses in an area with 500 possible channels, but typically maybe less than a 100 unique shows would be watched at any instant. A given physical channel won't show the same shows all the time - one day 84-1 maybe Discovery, then next HBO, but the cable box hides all that from the end user.
Originally Posted by MatWiz View Post
On the other hand, the TV station has no problem broadcasting one station HD stream over the air.
Depends on how you define "no problem." There's more to video quality than resolution. Each OTA station has bandwidth limitations too, and so couldn't broadcast a video equal in quality to blu-ray. Also, most OTA broadcasters choose to split up their bandwidth and offer addtional content, typically at 480i. Of the 7 major broadcasters in my area, each has one HD channel, but five also have at least one 480i channel. The stations with more channels have a lower bit rate on their HD channel, regardless of the resolution. For example, my local PBS station has three 480i channels - the 1080i HD channel comes in around 9Mbps (similar to the ABC channel). The local CBS station, without any subchannels, comes in typically around 16Mbps at 1080i, which is about the same bit rate I'll see from FOX (which uses 720p and has no subchannels)

The reason I use the Clear QAM instead of OTA is that the Clear QAM is already coming into my house due to me having cable for internet. I could setup a big antenna, but that'd just be extra work for no gain to me.
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Last edited by cwsqbm; 01-18-2013 at 07:33 AM.
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