Understanding Your Camera's
“The camera makes you forget you’re there. It’s not like you are hiding but you forget, you are just looking so much.”
In Aperture Priority mode, you set the desired aperture and ISO, and your camera will sets the shutter speed accordingly. Aperture is represented on your camera with an F-number.
If you look at the rear of your camera’s LCD screen you will see your current F-number. Slowly rotate your camera dial to change your F-number.
Photographers use Aperture Priority because they want to have control over the depth of field. Depth of field is the area in your photograph that appears to be in focus and sharp.
Tip! When in Aperture Priority mode one of things to watch out for is that the shutter speed may drop to a setting that’s too slow to prevent camera shake. If that happens, raise the ISO to ensure you have fast enough shutter speed, which will help you combat camera shake.
The photograph below was taken with a very shallow depth of field. The out of focus area in the background is known as bokeh.
In Shutter Priority mode, you set the shutter speed and ISO, and the camera sets the aperture accordingly. Shutter Priority comes in useful if you want to set a specific shutter speed to prevent camera shake.
It’s also handy if you want to set a fast shutter speed to freeze motion or a slow one to experiment with motion blur.
For the most part I use Shutter Priority for anything sports related and when I want to maintain a consent shutter speed for a particular scene.