What is Aperture in Digital Photography?

To begin with, Aperture as its english meaning says "an opening", is the opening in your camera from where the light enters. Now if you have a larger aperture, you get a brighter image and if its small, you have a darker image.

Having understood its basic meaning, we now move on to the technical details. Have a look at the image below which shows an Aperture in an SLR camera.

The image on right shows aperture as is faintly visible in a Digital Camera. (do not worry if you can't see it in your camera, just understand the concept !)

An important thing related to aperture is DOF(depth of field). Remember, the aperture also determines how many of the incoming rays are actually admitted and thus how much light reaches the image plane (the narrower the aperture, the darker the image for a given exposure time).

Picture this: you are taking a portrait picture. You focus the lens on the subject's eyes. Behind him is a tree. If you set the lens at a large aperture (small number) the tree behind him will not be in focus. If you use a small aperture (large number) the tree will be in focus. This byproduct of adjusting the size of the aperture is referred to as 'depth of field' and translates into the depth (or distance) of the area which will remain in focus for a given aperture and focus distance.

Note: how the depth of field has been kept small and so the farther images are not clear while nearer ones are very clear

The creative utility of adjusting the depth of field should immediately be apparent. By changing how big a part of the photograph is in focus, you can control exactly which details show up, and which do not, allowing you to lead the viewer's eye anywhere you wish.

Selecting proper Aperture Values are very important

Now having learnt the two most important concepts, lets move on to the Shutter Speed in Digital Photography.

For further explanation regarding anything related to Aperture, its settings, types and any practical problems, just leave a comment below and i will try my best to elaborate it here itself.

Cheers,

Kumar