Re: Newbie Apple IIgs questions

[Mitchell Spector <mitch2gs@hotmail.com>]

"Michael J. Mahon" <mjmahon@aol.com> wrote:

>David Murray wrote:
>> Secondly, I get color once the OS starts loading, but for some reason the 
>> control panel wouldn't give color.  Of course, I was surprised to see that 
>> same nasty color-phase-shift problem that older Apple's suffered from.  I 
>> thought surely by the time the IIgs was out Apple would have fixed that 
>> problem.  That is such a disappointment.  I'll try building that adapter to 
>> connect to my Amiga monitor's RGB input and I can pray that maybe it will 
>> look better there.  
>
>The color "aliasing" that you see on a composite video display is
>not an "error", but the correct functioning of the method used to
>create a color display.  It's just that in a text display, for example,
>you'd rather not see the colors.
>
>Intrinsic color bandwidth limitations of a composite video signal
>prevent producing high-resolution color images.
>
>RGB is totally different, and you will see exactly what you hope for.

    While that's true of composite, it's worth noting the IIgs does not 
produce a standard composite signal. The end result is something
actually sub-par and few steps below composite.

    Good example: Look at the fonts displayed inside a Finder window
on a TV set and the text actually appears in heavy bold (by no means 
subtle) bands of green, blue, purple and orange. The whole screen is 
quite literally a rainbow colored mess. Now switch over to output from a 
Video Overlay Card (which produces a corrected composite signal) 
and the black text appears greyish black. Any traces of color shifting
is subtle and faint, you really need to stare closely at the screen.

    Another example. Look at a checkerboard pattern of black and white 
pixels (say the background pattern in PaintWorks Plus). From the IIgs's
built-in composite port you get alternating patterns of blue and orange 
bars which blend to look purple. The Video Overlay Card shows it as a 
solid grey background (normal for composite to blur it that way).

>A separate luminance-chrominance video signal (as used by some C=64
>systems) can support better monochrome resolution and less color
>artifacting.

    I've used my Commodore 64 with both the split chroma-luma (essentially
S-Video) and regular composite, and even the latter produces a superior
video signal compared with the IIgs's composite-out. The same is true with
my Amiga, Nintendo, Super Nintendo or any other composite device.

    Interesting, the color artificating appearing in Super-Hi-Res composite
should be green, blue, purple and orange (I never really looked closely at it
until now). Sound familiar? :)

Mitchell Spector