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* Probably best to use this for your master frames, then crop/resize as needed for movies of other resolutions/aspect ratios.
If you have to choose something less usual, there is a nice diagram showing other options here: http://en.wikipedia.org/wiki/File:Vector_Video_Standards.png.
Preview Resolution:
In ParaView, the aspect ratio of what you see in the GUI may not match the aspect ratio of the display where your final movie will be displayed. If these don't match, then the image you see in ParaView won't match the image you see in your movie frames. To avoid this problem, you can lock the 3d window's resolution via "Tools -> Lock View Size Custom...". Now, what you see (except for overall size) is pretty much what you get. Even if you save movie frames at another resolution, if they have the same aspect ratio, you will get an accurate sense of the final appearance by looking at the locked 3d view in ParaView.
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