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Old 15th April 2010, 23:15   #206  |  Link
wonkey_monkey
Formerly davidh*****
 
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Join Date: Jan 2004
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Quote:
The reason Deshaker's preset is appr. 0.912 instead of appr. 0.909 is because I was convinced by that web page, but since most video applications out there seem to use 0.909 I may reconsider, even if it's not correct.
AIUI, 702 (which would lead you to a PAR of 0.912 for NTSC video) is the "correct" width only for PAL video, whereas NTSC uses 704 pixels:

PAL: 576/(702*3/4)=1.09402
NTSC: 480/(704*3/4)=0.909091

Both the NTSC values we're discussing (0.909, 0.912) do account for NAB, but different amounts. If you don't account for NAB at all, you end up with 0.888, and only careful experimentation will tell you whether your camera is made up "correctly" (the difference is, at most, less than 3%).

David
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