An NTSC Atari looks good on a PAL TV. How come?

[Geoffrey Oltmans]

On Wed, Mar 7, 2018 at 2:06 AM, Terry Stewart via cctalk <
cctalk at classiccmp.org> wrote:

> Hi,
>
> The PAL vrs NTSC TV standard complicated things when collecting home
> computers from other countries.
>
> In New Zealand we are on PAL.  PAL Atari 800s are rarer in the world that
> NTSC ones.  That being the case I recently settled on an NTSC one for my
> collection.  Hooking it up to a couple of my PAL TVs (via composite video)
> I was surprised to see a reasonable colour image.  I then dropped in a UAV
> video enhancement board and was surprised to see a very good colour image!
>
> I'm assuming it's because composite input into "relatively" modern can
> handle NTSC and PAL?  Is this a reasonable thought?  The UAV is not an NTSC
> converter, and even the inventor was surprised this worked.
>
> Those interested can read about the adventure here:
> https://www.classic-computers.org.nz/blog/2018-03-06-
> Converting%20-NTSC-Atari-800-for-PAL-using-UAV.htm
>
>
>
As others have said there are many sets on the market today that can do
either/or because supporting one vs the other is a "gimme". However, one
thing you may run into with PAL vs NTSC is that many games depended on the
video refresh timing of 50 or 60 Hz to work correctly and were hardcoded to
work with one or the other instead of determining the correct timing at
runtime. This can cause incompatibility problems with some software.
Another issue with other systems with more display memory (i.e. Atari ST or
Amiga) is that the PAL screen resolution tended to be a few lines higher
which can crop the image off at the bottom when running software designed
for PAL in NTSC mode. The timing problem is a real issue with a lot of C-64
software that you run across since a lot of it on the 'net assumes PAL, so
I ended up converting my Commodore 128D to a PAL system with a PAL VIC-II
chip and the various load option changes (oscillator, etc). Problem I have
now is that I'd rather use a CRT monitor, and most all that were sold in
North America can do only NTSC, so I'm stuck with black and white.