My questions are: why is there overscan on flat panels? Many HDTVs take a 1920x1080 image, upscale it to about 2016x1134, and crop out the center 1920x1080. Absolutely stupid!
Blame closed captioning. With analog video, closed captioning is sent as data at the very top of the picture. This appears as white blocks moving around the top. With analog TVs, the over scan was enough to hide this data, but with digital TVs you have the ability to actually display the entire picture including this annoying noise at the top. Most viewers don't like seeing moving noise at the top of the screen, so manufactures naturally set the TV to crop it out. This is becoming less of an issue with more video sources being digital and never having the analog CC data added to the picture in the first place.
that white noise you see on top of a analog signal is not just CC as that happens on line 21 on analog TV and on line 9 on HD tv.
That bar will always be their because it not only hold close caption content but it will hold the AFD. It also hold time code and other information the networks need to know that is their as a quick reference.
I'm a Home Theater Rep at a big box store. One of the Toshiba reps came by one day and mentioned the 'native mode' that Toshiba TVs have available to them. The overscan is simply a throwback (on other tvs) to how images were displayed on crt televisions, where as native mode takes the entire image and displays it as is, without the overscan. I did ask why it wasn't a standard feature on lcd tvs then, but he couldn't answer that.
This is helpful stuff, Ben. It would be good to have more of these kinds of primers in the future.
So am I correct in understanding that a Blu-ray disc will look best when displayed on a 1080p flat panel with the overscan feature turned off? It sounds like there won;t be any unnecessary upscaling and cropping this way.
Indeed. I was really blown away by the difference I saw when I calibrated XBMC to display without overscan on my 51" 1080i screen. As if Comcast's low-bitrate "HDTV" isn't crappy enough, we have overscan to contend with...
That is correct gunnar. 1080p and no overscan means no altering of the image on the disc.
My question is why didnt they use a better image to show this off, one where edge stuff would get cut off in zoom levels and it would be easy to say "see, the monkey on the edge is now not visible".
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My questions are: why is there overscan on flat panels? Many HDTVs take a 1920x1080 image, upscale it to about 2016x1134, and crop out the center 1920x1080. Absolutely stupid!
Great question, maybe it'll be the next question addressed.
Blame closed captioning. With analog video, closed captioning is sent as data at the very top of the picture. This appears as white blocks moving around the top. With analog TVs, the over scan was enough to hide this data, but with digital TVs you have the ability to actually display the entire picture including this annoying noise at the top. Most viewers don't like seeing moving noise at the top of the screen, so manufactures naturally set the TV to crop it out. This is becoming less of an issue with more video sources being digital and never having the analog CC data added to the picture in the first place.
@Jeff
that white noise you see on top of a analog signal is not just CC as that happens on line 21 on analog TV and on line 9 on HD tv.
That bar will always be their because it not only hold close caption content but it will hold the AFD. It also hold time code and other information the networks need to know that is their as a quick reference.
I'm a Home Theater Rep at a big box store. One of the Toshiba reps came by one day and mentioned the 'native mode' that Toshiba TVs have available to them. The overscan is simply a throwback (on other tvs) to how images were displayed on crt televisions, where as native mode takes the entire image and displays it as is, without the overscan. I did ask why it wasn't a standard feature on lcd tvs then, but he couldn't answer that.
This is helpful stuff, Ben. It would be good to have more of these kinds of primers in the future.
So am I correct in understanding that a Blu-ray disc will look best when displayed on a 1080p flat panel with the overscan feature turned off? It sounds like there won;t be any unnecessary upscaling and cropping this way.
Indeed. I was really blown away by the difference I saw when I calibrated XBMC to display without overscan on my 51" 1080i screen. As if Comcast's low-bitrate "HDTV" isn't crappy enough, we have overscan to contend with...
That is correct gunnar. 1080p and no overscan means no altering of the image on the disc.
My question is why didnt they use a better image to show this off, one where edge stuff would get cut off in zoom levels and it would be easy to say "see, the monkey on the edge is now not visible".