Re: IIGS -> VGA: Success!

["Jim Maricondo" <jimm@NOSPAM-uranus.dti.ne.jp>]

"Michael J. Mahon" <mjmahon@aol.com> wrote in message
20020819044504.28100.00001679@mb-fi.aol.com">news:20020819044504.28100.00001679@mb-fi.aol.com...
> The photos may help, but it's hard to do an A-B comparison when the A
> is missing!  ;-)
>
> In this case, the A from which we all start is the normal Apple RGB
monitor
> for the IIgs.
>
> I really don't expect to see any more pixels from a VGA monitor (!),
though
> it would be nice to see crisp ones.  The problem which is attributed to
the
> "dot clock" may arise from the natural jitter of the video sampler when
> sampling a video signal (Apple II) whose dot rate is not rationally
related
> to the sample rate is present.  Remember that the timing of the Apple II
> video signal is not exactly NTSC, and is almost certainly not on the pre-
> defined internal "menu" of the XRGB-2plus.
>
> I am interested in whether you would prefer the display on a VGA display
> to the display on the native Apple RGB monitor.  In other words, if I
don't
> care whether I use one display or the other, which looks better, and why?

That is an interesting point that you bring up.  The XVGA-2/plus is supposed
to be preprogrammed for standard NTSC dot clock (and even allows a user
adjustable dot clock), but it doesn't quite work perfectly with the IIGS's
funky signal.  The XRGB-2plus I think is just slightly "off"; this is
because the on screen menus themselves aren't perfectly sync'd (even without
any input signal!)  However, the XRGB-2's on screen menus looked perfect on
the CRT I saw at the store, but on my LCD display, they are 95% as good
(just a small bit of waviness).

I will upload instructions and a photo as soon as I find the time (hopefully
very soon!).  The XRGB-2's output is quite crisp, however, I would still say
the IIGS monitor is best!  (I would say the XRGB-2 is maybe 90-95% as good,
and the XRGB-2plus maybe 80-85% as good.)  But to me, using a VGA display
more than makes up for that 5%!  And I have a feeling though that the
XRGB-2's output might be even closer to 100% if I were to try it with a real
CRT, and not just my LCD (which is adding yet another ADC phase!)  It seems
to me that it would be tough to find ANY device other than the AppleColor
RGB Monitor that has the exact right dot pitch and output characteristics to
make 640x200 dithered pixels look as good as they do on the IIGS.  Do you
disagree?

 -Jim