Depth of Field

1. Controlling DOF

1.1. our eyes, aperture, and focal distnave are the main factors that determine how big the circle of confusion will be on your camera's sensor

1.2. Larger aperture and closer focusing distances produce a shallower DOF

2. Depth of Focus & Aperture Visualization

2.1. called focus spread

2.1.1. differs from DOF, describes the distance over which light is focused at the camera's sensor as opposed to the subject

2.2. When an object is in focus, light rays originating from that point converge at a point on the camera's sensor

2.2.1. if the light rays hit the sensor at slightly different locations then the object will be rendered as out of focus

3. refers to the range of distance that appears acceptably sharp

4. does not change from sharp to unsharp, but occurs in a gradual transition

5. Circle of Confusion

5.1. how much a point needs to be blurred in order to be perceived as unsharp

5.2. when the circle of confusion becomes perceptible to our eyes, it is said to be outside the DOF and no longer "acceptably sharp"

5.3. DOF only sets a maximum value for the cirvle of confusion and does not describe what happens to regions once they become out of focus

5.3.1. regions called "bokeh"

5.3.1.1. two identical images with identical DOF may have significantly different bokeh