[geeks] Whee! Lightning strikes, AGAIN!

[Phil Stracchino]

gsm at mendelson.com wrote:
> On Wed, Jul 29, 2009 at 10:46:37AM -0400, Phil Stracchino wrote:
>> Not for nothing is NTSC sardonically known as Never The Same Color...
> 
> That's for a different reason. The color signal was transmitted a phase 
> encoded 3.57 mHz signal overlayed with the video signal. The phase is reset
> to "zero" at the end of each field. 

But chroma sample sharing is a significant factor in NTSC's notorious
color-fringing, not so?

> Due to transmission errors, reflections, etc, the signal wanders a bit,
> although most color errors were really caused by poorly set up equipment.
> 
> The BBC who did not start transmission of colour until 1965 learned from
> the experience of the NTSC broadcasters and every line inverted the phase 
> effectivley reseting it to "zero". 
> 
> That's where the name came from, PAL (phase alternating line).

Yup, I know.  A simple but clever solution that automatically
compensated for the most common causes of color drift.


-- 
  Phil Stracchino, CDK#2     DoD#299792458     ICBM: 43.5607, -71.355
  alaric at caerllewys.net   alaric at metrocast.net   phil at co.ordinate.org
         Renaissance Man, Unix ronin, Perl hacker, Free Stater
                 It's not the years, it's the mileage.