Re: Apple IIGS monitor replacement

limtc <thyechean@xxxxxxxxx> wrote:

Now I get my system disk for my GS, I am faced with another problem:
the LCD TV is not suitable for anything 640 mode or 80 column - - they
looks like double hires! If you still remember double hires, basically
it is 560x192 monochrome or 140x192 with 16 colors... so basically
when you show a DHR mono image (says Instant Pascal) on a color
monitor, it is just color everywhere and looks very bad.

What you're seeing is color shifting or artificating, an idiosyncrasy
of composite video. It doesn't necessarily mean what the Apple IIgs
is displaying is normal for composite--far from it. Look at other systems
displaying 320x200 with hundreds or thousands of colors in its palette
(e.g. Amiga, Super Nintendo, Nintendo 64, Sega Gensis/Saturn); with
their composite output there's NO problem.

I believe it's a flaw in the video design of the IIgs. RGB video is fine,
but composite is a mess (excluding emulated 8-bit Apple IIe video).
Apple did quietly offer a solution/fix, that was to purchase and install
their Video Overlay Card. You get respectable composite video with
that, without any of the massive color shifting and color inaccuracies.

I took some quick snapshots to (roughly) show the difference:

Apple IIgs composite-out (built-in port):
http://raptor.golden.net/~mspector/IIgs-composite.jpg

Apple IIgs composite-out (Video Overlay Card):
http://raptor.golden.net/~mspector/IIgs-VOC.jpg

Apple IIgs RGB-out (AppleColor RGB):
http://raptor.golden.net/~mspector/IIgs-RGB.jpg

Sorry about the poor quality, this is my Sony 27" TV set from 1989
snapped with a cheap digital camera. Notice how the Video Overlay
card output gives you readable text in the Finder desktop. And
although you can't see it here, it's also more accurate for color.
Obviously the RGB monitor is the nicest output of all.

Surpringingly my PowerMac 7200/120 monitor (which is a 14" I think),
display Apple IIGS graphics on 640x480 mode using Bernie PERFECTLY.

This is because it's software emulation, it's no different from looking
at a static JPEG image on your Macintosh in Photoshop for MacOS.
You're looking at the Macintosh generate a *simulated* picture video
of what an Apple IIgs looks like, it's not the real thing.

Now I wonder why there are all talks to use GS on a VGA monitor, etc,
but not to a Mac monitor? This is the closest to a GS experience I
think. At least Mac monitor might be easier to locate than GS monitor.
I will be glad to use 7200/120 for my GS if it is indeed possible.

They're the same technology, a Macintosh monitor *is* a VGA monitor
more or less. The only difference (generally) is the pin connector, which
is why I can hook up a PC display to a Mac with a pin adapter, or visa-
versa.

The Apple IIgs won't work with a Mac or PC monitor though because
their scan frequency is double or more what the IIgs outputs at, and
they cannot synchronize down (slow their scanning frequency) to match
the GS. There are older VGA displays that are backwards compatible to
15.75 kHz (what the IIgs requires), I have a NEC MultiSync 3D and a
Sony CPD-1302 that work on my Apple IIgs's, Macintoshes and PC's!
I really should get rid of one, I don't have much storage space anymore.

The NEC and Sony monitors work nicely, but I find their colors aren't
as rich as the AppleColor RGB. Mind you, they are much sharper and
of course larger too. The dithering in the 640 mode is a more noticable
(you can see the patterns making up colors, they're not solid anymore)
but at least you get rounded pixels. The Second Sight video card on
the other hand gives you those ugly square looking pixels you used to
see in PC games in the early 90's, although that's the least of its problems!

Or is there a way to force the GS to display 640 mode in monochrome...?

Absolutely. Go into the Control Panel, choose the 'Display' option.
Under "Type:" switch it to 'Monochrome'. This *only* has an affect on
composite output, it does absolutely nothing to an RGB display.

On a color composite display (like a television set), everything will
show up in black and white. If you use it on a monochrome display,
such as an Apple Monitor II or ///, you get colors displayed in 16
shades of green or amber. As opposed to ugly line patterns. Hope
that helps you in the meantime.

Mitchell Spector
.

Relevant Pages

  • Re: still no resolution solution..
    ... & still unable to achieve 1600x1200 display, ... motherboard w/ sapphire radeon 4650 video card. ... driving a dell m782 monitor (same monitor was ... Module "ddc" already built-in ...
    (Fedora)
  • Re: Plugging TV into Dimension 5150?
    ... right of your current monitor. ... When you go back into settings, does it say they are both enabled? ... When you go into display settings, does it show one monitor or two? ... video etc. to a dvd. ...
    (alt.sys.pc-clone.dell)
  • Re: Plugging TV into Dimension 5150?
    ... See if when you move your mouse if you can move it off your PC monitor ... When you go into display settings, does it show one monitor or two? ... video etc. to a dvd. ... The TV does not have the s-video. ...
    (alt.sys.pc-clone.dell)
  • Re: Plugging TV into Dimension 5150?
    ... See if when you move your mouse if you can move it off your PC monitor ... When you go into display settings, does it show one monitor or two? ... video etc. to a dvd. ... The TV does not have the s-video. ...
    (alt.sys.pc-clone.dell)
  • Re: Apple IIgs Color Dither Problem
    ... for VGA monitor is connected to Apple IIgs' RGB port. ... the frequency of the 640 dot clock in the video signal of an Apple IIGS results in scans that exceed the resolution of the original AppleColor RGB Monitor that Apple sold for their machines. ... Because the resolution of the video signal was higher than the resolution of the monitor used to display it, the effect was that adjacent pixels on a 640 display "blurred" together resulting in the mixing of pixels by the monitor hardware itself to produce tertiary additive colours. ...
    (comp.sys.apple2)