Depth of Field is the measurement of how much of your image is sharp, and is controlled by Aperture and Distance to subject.
The closer you are to your subject, the less sharp your background will be.
Aperture decides the amount of Bokeh (Boh-Kuh), or, real technical term here: fuzzyness, that your photo has.
In the photos below, we photograph a rose tree at f/22 and at f/2 to show you the difference in Depth of Field.
We first metered the scene, using the Pocket Light Meter app.
Then we set up the camera for the Composition we want.
We then set the camera to match the meter reading.
And finally, we get the shot that we are looking for.
This photograph has a very shallow Depth of Field so that the subject is isolated from the busy background.
If we wanted to have the background seen, the we could try again with the aperture set to f/22.
The difference is huge.
We like the shot that was taken at f/2 because it draws attention to the subject of the photograph, the Rose.
We took the same photo again in Automatic Mode, just to see what the camera did.
While Automatic Mode did OK, I feel that the photo is under exposed by about one stop. Try this sometime while shooting in to the light. The Automatic Mode tends to expose for the brightest parts of your scene, killing all of the shadow details.
Do yourself a favor, just shoot Manual, over and over, until you are comfortable with your camera.
In case you are wondering about the setup we used for this shot: Canon 6D Camera, Canon 50mm f/1.8 (AKA: Nifty Fifty), Induro Adventurer Tripod.
If you have any questions or comments, feel free to ask!
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