> 	A small typo here: PAL is 720x576. NTSC is 720x480 which translates
> to the same pixel rate given the difference in fps. You should note
> however that TV pixels are not square and that the screen aspect
> ratio is 4/3 for both PAL and NTSC even though neither 720/576 nor
> 720/480 is 4/3.

This is incorrect. Both for PAL as well as for NTSC the aspect ratio is 4:3! 
  The pixels are just, as you noted, not square. Thisis the 
essentialdifference for digitalformats in use today.

For square pixels, you need an image that is 786x576 pixels (for PAL). This 
is the correct resolution to render the image for POV-Ray in as long as the 
TV station doesn't give the original poster any more precise instructions. 
They will certainly be able to deal with that size.

If he would create an image 720x576,it would be really hard to get it to 
look right as POV-Ray does not preview non-square pixels (computer screen 
pixels are square these days). Nevertheless, after setting up the image with 
768x576 (square) pixels, it would be rather trivial to get non-square 
pixels: The final render should be made using the same 4:3 aspect ratio, but 
rendering to 720x576 pixels. Of course, all this assumes the TV station 
cannot handle 786x576 - it would be rather unusal if they can't.

	Thorsten

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