I would like to encourage all of you out there to take your camera out of Auto and try one of the manual settings. To encourage this I am going to walk through the different settings and how they work. The camera I'll use for the example is a Canon EOS 5D Mark III.
Today we will start with the AV setting. Do you see it on the dial bellow?
This is the setting I use the most. It puts me in control of the Aperture (f-stop) and allows the camera to decide which shutter speed to use (more on that latter). Both of which control the amount of light allowed to reach the "film," each in its own way.
In high school we learned our f-stops with our hands, still to this day when I explain f-stops to someone I use my hands. Here's how it works, make the smallest circle you can see through with your thumb and pointer finger, that is the equivalent of f22; it allows in a very small amount of light. Then make the biggest circle you can with both of your hands, that is the equivalent of f1.4; it allows in a lot of light.
Having control of the aperture allows you to control what is in focus and what is not, or the depth of field. Here is an example of a small and large f-stop.
The first photo was taken with and f-stop of 1.8, while the second was taken at f22(this is the form f-stops are written in). You can see the difference between the two photos (besides one being of a drink and one a landscape). On the first photo I have shown you what is important by selecting what to focus on. Where as the second photo everything is in focus, there for I want you to see the whole area. These examples are quit different in subjects but its just to get the point across. Changing the f-stop allows the photographer to decide what is important and make it be in focus.
All of this will allow you to have more creative control of your images. Get out there and experiment!
Coming up next, the TV setting.