you cant render dv at 1024x768- sure you can tell after effects - but it doesnt do anything.
dv only works at 720x576 - it is fixed size and fixed data rate. around 5:1 compression - which is quite good.
http://en.wikipedia.org/wiki/DV
DV uses DCT intraframe compression at a fixed bitrate of 25 megabits per second (25.146 Mbit/s), which, when added to the sound data (1.536 Mbit/s), the subcode data, error detection, and error correction (approx 8.7 Mbit/s) amounts in all to roughly 36 megabits per second (approx 35.382 Mbit/s) or one Gigabyte every four minutes.
There isnt any difference- they are the same. identical
dv-ntsc works at 60hz and has a slightly difference image size.
you didnt look in the right place. or misunderstood codecs and their function in the workflow.
i believe imovie only works with dv files.
aftereffects has output codec settings that can do anything.
you have to work with what your system can do-
sure the projector has a native resolution -
but often its not practical to work at this resolution- or doesnt actually produce any visibile difference at all.
sure you can do higher def - but making it all work tends to cost more money higher spec machines, faster discs.
you might be surprised if you actually knew that the resolution of tv signals is really only around 320x240 or thereabouts - and all these years you never really noticed.
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zooming in- when there is often no detail to zoom in on - is an artistic decision really. does the zoom look ok? its really an artisitic not a technical judgement.