Depth of Field Pt. 1
Depth of field is like a block of sharpness which extends into your photo. You might need a big deep depth of field for something like a landscape, or maybe a small shallow one for a portrait with a soft fuzzy background.
You can choose how deep into the image the block of sharpness extends but to do it you have to understand how to combine depth of field with where to focus if you want to control image sharpness.
Aperture size is the main depth of field control - but focal length and how far away you are from the spot you've locked your autofocus onto also makes a difference. As you adjust depth of field with your aperture you must be careful to avoid camera shake - which can happen when you set a small aperture.
In this video exercise we'll work with a wide or short lens because different focal length lenses have different depth of field characteristics. A short lens has lots of DOF. In depth of field part 2 well do it with a long lens which is much better for fuzzy backgrounds because they have a much shallower depth of field.