Re: Double HIgh Resolution Question

[Andy McFadden <fadden@fadden.com>]

Eric Smith <eric-no-spam-for-me@brouhaha.com> wrote:
> mjmahon@aol.com (Michael J. Mahon) writes:
>> I have not examined the logic that synthesizes RGB outputs
>> from the composite luminince-chrominance signal synthesized
>> by the Apple, but I would be surprised if it took much of the
>> following 4-bit group into account when determining its current
>> outputs.
> 
> Yes, that's why some Apple displays look different on a composite monitor
> on than on an RGB monitor.  The logic to produce RGB does not 100% faithfully
> model the behavior of NTSC composite video color decoding.


Yes indeed.  I can't remember it now, but I found examples of pixels that
would change appearance when the pixels that came after them changed.
(This is based on staring at the screen through a magnifying glass -- I
didn't believe it either at first.)

I believe one of the DHR images on the CP samples disk has what looks
like some scattered pixels.  This was part of my experiments.

FWIW, I use one of those Magnavox monitors that Resource Central was
selling way back when.  It has both RGB and composite inputs, so I was
actually using the same monitor for both RGB and composite (just push
a switch to change modes).

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