Aperture refers to the diameter of the hole that lets light into your camera. It also controls what is and isn’t in focus in your photos. Selecting the Av function on your camera lets you have control over the aperture value of your photo allowing you to have a correct exposure. The dial on your camera can be rolled to the left or the right which increases or decreases the aperture value, thus making the hole wider or narrower. The lens allow the range of the aperture values to differ. Choosing the lowest possible aperture value will make the image have a very shallow depth of field or little depth of focus in the photograph. For example: taking a photo of a cat with a house in the background with a low aperture value will make the foreground very focused, but the background very blurry. Having the highest aperture value is the opposite of this. Using the same example, the cat and the house will now both be in focus and the area and depth of focus is increased by a large amount.
Most cameras come in different modes. This helps the user to capture an image however they like. If the user is overwhelmed by the amount of settings on the camera or if they have little experience with it, they can switch the camera to auto or program mode which will change values for them. If you are more comfortable with the camera, you can even switch it too aperture priority mode which allows you to manually change the values of the F-stop (Av) by using a dial on the camera. Aperture is defined in the paragraph above. For photography with a lot of movement like a sport or wildlife photography, the best mode to use is shutter priority mode (S or Tv) with ISO to give you complete control over shooting moving objects. Higher shutter speeds will allow you to capture more precise and crisp images but it is used more often in daylight where this is more possible. When it gets darker however, a lower shutter speed is more optimal as it allows the camera to collect more light since the image is exposed for longer. This will create a brighter image although it is dark. The slowest shutter speed possible is the best since it produces the highest quality image and the final image won’t result in unnecessary blurry shots. Night photography especially, requires manual mode which will allow the photographer to have absolute control and freedom when using the camera. This will allow them to adjust everything mentioned above. The ISO, aperture value and shutter speed. Auto mode is bad for night photography as it might use a very underexposed shutter speed or very high ISO, resulting in bad quality images.
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