Originally Posted by TVOD
Unless I'm missing something, I only see mention of 4:3 and 16:9 video aspect ratios. But the non-square pixel issue was a hassle when computers were used in the SD days. I remember 9/10 being used for 4:3 as it needed to go back to video and fill the 720 pixels. HD was around by the time 16:9 was in common use. Where was the mention of other aspect ratios for video delivery?
They're saying the pixel aspect ratio / frame aspect ratios in certain video programs changed (around 2009 and Final Cut pro around 2010?), because presets weren't correct (squares not really coming out square?). Though I'm not sure I really believe it (I'm not really sure the changes they've made are correct). Surely it depends how DVD/Blu-ray players and TVs upscale the SD formats to HD - and the TVs are 1.78:1 approx.
"I remember 9/10 being used for 4:3"
And they say that has now changed from "0.9" to "0.91" for "D1/DV NTSC" (value in CS4 is 0.91, previous value 0.9)
They say (in the above link) things like "PAL D1/DV Widescreen square
-pixel equivalent" changed (from version CS4) from "1024x576" to "1050x576". So for square pixels, where PAL widescreen stuff was done at 1024x576 (1024/576=1.777 so about 1.78:1) aren't they now saying PAL widescreen stuff should be done at 1050x576 (1050/576=1.823 so about 1.82:1). If you select the "PAL D1/DV Widescreen Square Pixel" preset in AE CS4 it is "1050x576" square pixels. and it says the "Frame Aspect Ratio" is "1.82".
"Remember that your original 16×9 image (1024×576 pixels) is only going to occupy the middle part of the TV screen...So your original (square pixel) After Effects compostion needs to be 1024+13+13 pixels wide. Namely, 1050×576
to guarantee that it maps correctly on to the 720×576
They say (for non
-widescreen PAL), "if you previously created 768x576 square-pixel footage items to use in a PAL D1/DV composition, you should now create those items with square-pixel dimensions of 788x576". (768x576=1.33:1, 788x576=1.37:1 frame aspect ratio).
They say the pixel aspect ratio changed in other video programs around that time too "UPDATE: See this post
for the news that Final Cut Pro 7 uses the corrected pixel aspect ratios, too. And see this thread
for information about the Foundry making the change as a bug fix in Nuke.".