I'm shooting unlimited hydroplane racing today. Where I positioned the boats are going to round a turn (coming right at me) and then race past me (good opportunity for a panning shot). I was thinking about switching between Tv (fast shutter speed) to Av (slower shutter speed) as the boat is moving around the corner and then past me. Not sure if I'll have time to do this or not. But I was wondering if anyone else has tried this? (probably a crazy idea)
If I remember correctly the camera (Canon 5D MkII) will save the shutter/aperture settings for each mode. I'll have lots of time for testing so today should be fun.
EDIT: Forgot to mention I'm shooting with a borrowed 100-400 L so I'm not sure what shutter speed to use for panning at 400mm. 1/250?