Re: [stella] Interlacing Success!

Subject: Re: [stella] Interlacing Success!
From: Chris Wilkson <ecwilkso@xxxxxxx>
Date: Tue, 20 Aug 2002 02:16:29 -0400 (EDT)
On Sun, 18 Aug 2002, Andrew Davie wrote:

> In conclusion, the usual 2600 scanline is equal to exactly TWO NTSC
> scanlines.  And yes, you can cut that in half.  Your belief that a TV
> displays only 262 lines (or 312 PAL) is probably the issue.  In any frame,
> yes - there are roughly that many lines - but TVs draw pictures in
> interlaced mode - where an actual image is composed of two frames - the odd
> lines first, then the even lines on the next frame.  Each of those frames
> being 262 lines (or 312 PAL).  Thus giving our actual TV resolution of 525
> NTSC (625 PAL).

Yep.  One small nitpick though.  Each FIELD has 262(.5) scanlines.  There are
2 fields (even and odd) in each FRAME (total of 525 lines).  There are 60
fields per second, and 30 full frames per second.

Wish I could follow this thread more closely.  But I haven't got a computer
or a connection at the moment.  :(  Anyway, keep up the good work everyone!
Oh...and one more note.  These demos won't be producing true NTSC interlace
due to the lack of proper equalizing pulses and vertical sync serrations.
So be careful when trying tricky stuff like may or
may not work.


Archives (includes files) at
Unsub & more at

Current Thread