Re: monitors & video cards

[P3D Greg Marshall <greg.marshall@xxxxxxxxxxxxxxx>]

I wrote:
>> Yes, a non-interlaced
>> monitor will generally display an image from an interlaced
>> source, but it may not get the interlace right.  That is, each
>> field will show on top of the other rather than vertically
>> offset (interlaced).

Andrew Woods wrote:
>Sorry, this is simply not true.  An interlaced video signal determines
>the position of the odd and even fields by the relative timing of the
>horizontal and vertical synchronisation signals.  The monitor 
>would need to do something extraordinary to defeat the interlacing
>generated by the video source.

I don't want to get into a debate on this point because it isn't worth
it.  And you are correct that interlacing pretty much just happens
as a result of the relative timing of H and V sync signals. BUT, it
is most definitely true that many monitors do not handle inter-
laced sync well at all:  The scan lines tend to "pair up" rather
than interlace.  I'm not a monitor engineer, so I can't say why
this happens.  If you're interested I can ask a guy I know who
has been designing monitors since long before computers
would fit on a desktop.

Greg Marshall


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