Photographic Techniques and Artifacts

Cayley BlennerPhoto 1

January 2012

Shallow Depth of Field

Shallow Depth of Field

» Definition: Shallow depth of field is the range of distance within a scene that is sharp, small, or covering a smaller depth in the scene.

» Aperture will be wide.

» Aperture value will be small, such as f/1.8.

» Lens opening will be wide.

Deep Depth of Field

Deep Depth of Field

» Definition: Deep depth of field is when an image is sharp from front-to-back.

» Ways to affect depth of field is to change the distance of the camera to the subject. To increase the depth of field move back. To reduce the depth of field, move closer.

» A small f-stop (like f/11) on a 35-70mm zoom set to

35mm gives a deep depth of field. (from six to 20 feet with the lens focused at 9 feet)

Fast Shutter Speed

Fast Shutter Speed

» Definition: Fast shutter speed is used to produce the effect that movement has been frozen. The subject must be moving, and the camera still.

» Shutter speed is measured in seconds- The bigger the denominator the faster the speed. (ex. 1/1000 is much faster that 1/30).

Slow Shutter Speed

Slow Shutter Speed

» Definition: Slow Shutter Speed is used to get a somewhat moving picture. This is because as you take the picture objects around you may be moving.

» Use a sliw shutter speed and follow the subject as it moves pressing the shutter button as you pan. Your subject will appear sharp, making it appear as id it hasent movedposition, but the background will be blurred making the subject look like its hurtling along.

» Keep camera at a fixed point, choose a slow shutter speed, the press the shutter button. By using this technique the background will be sharp and the subject will be blurred as it passes across the view finder.

» By choosing slower shutter speed (4 seconds, f/3.2), walking people in the background have been eliminated. You can see a couple of “ghosts” in there.

Film Grain

Film Grain

» Definition: Film Grain is the random optical texture of processed film due to the presence of the tiny particles of metallic silver, or dye clouds, developed from silver halide.

» Digital photography does not exhibit film grain, since there is no film for any grain to exist within. The effect of film grain can be simulated in some digital photo manipulation programs, such as Photoshop adding grain to a digital image after it is taken.

Digital Noise

Digital Noise

» Definition: “Image noise” is the film grain for a camera. For digital images, this noise appears as random speckles on an image or otherwise smooth surface and can significantly degrade image quality.

» Types: » Amplifier noise » Salt-and-pepper noise » Shot noise» Quantization noise» Film grain » Anisotropic noise