NTSC and HD render of same project?


I’d like to be able to render the same animation in both NTSC and HD and was hoping someone can suggest the correct method of compensating for the lost top and bottom of the cameras view.

Can this be done without moving the location of the camera without any problems?
Reason being, I’m animating the location of the camera sometimes and would like to avoid redoing that.

35MM down to 28MM seems pretty close, but I can’t tell yet if it will cause any problems to change the lens.
Will the difference in lens size distort the shape of objects?

All thoughts are very welcome.