Re: What causes Vertical Stripes in GS/OS 6.0.1 desktop?

["Michael J. Mahon" <mjmahon@aol.com>]

Rob wrote:
> My GS monitor died so I hooked my //gs  up to a 32" Panasonic TV.  I"m
> using an RGB to Component video encoder with an adaptor cable I wired
> up to hook it to the  YCbCr inputs on the TV.   It looks great.  If
> you haven't tried it, playing GS games on a large monitor is like
> night and day in comparison to an old, small GS monitor.    40/80
> column text looks fine;  Apple II HI-Res games, DHR games, and GS
> games all look good. ...but the GS/OS desktop looks absolutely
> terrible.  The blue background and all folder icons have these ugly
> vertical strips or banding.   The stripes do not appear in any text or
> white/black portions of the display, just the background and folder
> icons.    Anyone know what is so special about the GS/OS desktop that
> might explain this?   Is it at a different resolution then most other
> GS apps and games?  Can this be changed?  
>  I could probable live with it but it's just odd that everything looks
> so nice and clear except for the GS/OS desktop.

The desktop background is a dithered, alternating blue-white vertical
line pattern in 640 mode, meaning that the pixel clock is 16MHz.

With many video resamplers, this results in a beat frequency that
produces the stripes that you see.

Although it is theoretically possible to eliminate this pattern,
the most common video resamplers (for LCDs, etc.) don't do so.

I'm afraid you'll have to live with it unless better resamplers
become widespread.

-michael

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