Shutter Priority or Aperture Priority?

Should you shoot in Aperture Priority (Av) or Shutter Priority (Tv) mode? If you want to show any object in motion choose Shutter Priority (Tv) mode :



In the above picture I wanted to show light trails of cars in motion. So I chose Shutter Priority with a shutter speed of 8 seconds. As the shutter remains open for a bigger amount of time the camera has to be on a tripod to prevent it from shaking which will blur the image.

To freeze motion choose a faster shutter speed :



To freeze the motion of the butterfly I used a shutter speed of 1/100 second (0.01).

PHOTOMANTRA : Slow shutter speeds to blur motion.