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Posted by MassiveProng on 01/18/07 12:57
On Thu, 18 Jan 2007 08:24:26 -0000, "M.I.5?"
<no.one@no.where.NO_SPAM.co.uk> Gave us:
>
>"Barry Watzman" <WatzmanNOSPAM@neo.rr.com> wrote in message
>news:45ae3543$0$4876$4c368faf@roadrunner.com...
>> Re: "overscan is an "attribute" of CRTs"
>>
>> No, wrong. All rear projection displays overscan at least slightly, even
>> if they are digital (this includes LCD and LCoS projection, as well as
>> DMD). In fact, overscan is effectively required by law (the law doesn't
>> actually require overscan, but it does require that the picture totally
>> fill the screen. It's an artifact going back to the 1950's and the days
>> of small round picture tubes, but it's still on the books). On a rear
>> projection set, regardless of the source of the projected image, the only
>> way to assure this is to slightly overscan the screen). There is not such
>> explicit control of the optics and the magnification ratio that the
>> projected digital display can be made to just exactly fill the screen, so
>> a slight amount of overscan is used .... the entire resolution (say
>> 1920x1080) is generated, but it's projected onto the viewing screen with a
>> very slight amount of overscan so that the screen is assured to be filled
>> on every single set coming off the production line.
>>
>> [In fact, digital displays using three-element LCD and LCoS even still
>> have convergence adjustments to overlap the 3 image elements exactly.]
>>
>> The only sets that don't overscan at all are direct view digital displays,
>> e.g. direct view (not projection) LCD and plasma.
>>
>
>That's actually not quite true Barry. They actually still do lose a small
>border area (for picture type video sources such as DVD). The only time
>they don't do it, is when showing video generated by a computer.
OR digital cable box, OR upconverted DVD player, OR HD DVD player,
OR...
>
>There is a very good illustration of this if you can get your hands on a
>copy of Buster Keaton's, The General in it's region 1 version. Apart from
>being a great film, if you play it on your chosen DVD video player onto a
>Plasma or LCD display, you will, well, get to watch a great film. But
>couple your PC's output to the display, and play it on the PC and repeat the
>exercise. The film material is almost wholy contained in the 'protected
>area' (because otherwise some of the subtitles would be lost) . The grey
>border is the area that is masked off when the normal video input is
>received.
You ain't real bright, boy.
>Other region versions are probably the same, but I haven't personally tried
>them.
Nor do you even know anything about what you DID try.
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