As I said you can only change the display proportions in the QT7 pro player.
I have no idea why you're seeing the image squashed in the QTX player. I see this
The inspector says it's 1440x1080, but the image display is normal widescreen.
Could it be because I'm in Apple ProRes 422 and you are in HDV 1080i50? I don't know
Yes. HDV 1080i is always 1440. ProRes can be anything. The codec in the QT player tells it how to display the video. HDV is also a much smaller file size and basically the same codec as the original, rewrapped into QuickTime.
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