In “Aperture Priority” mode, you manually choose the lens aperture while the camera chooses the necessary shutter speed for good exposure. You have complete control over subject isolation and can try with depth of field since you can adjust the lens aperture and let the camera calculate the correct shutter speed. If there is too much light, the camera will automatically raise the shutter speed, whereas if there is not enough light, the shutter speed will be decreased.
About Lesson