Digital still camera

EXERCISE-4: HANDLING AND USE OF DIGITAL STILL CAMERA

  • The process of producing images of objects on photosensitive surfaces is called photography. A photographic method that stores the image digitally for later reproduction is called digital photography.
  • A digital camera (or digicam) is a camera that takes still photographs or video, or both, digitally by recording images via an electronic image sensor.

Types of digital cameras

  • Digital cameras are made in a wide range of sizes, prices and capabilities. The majority are camera phones, operated as a mobile application through the cell phone menu. Professional photographers and many amateurs use larger, more expensive digital single-lens reflex cameras (DSLR) for their greater versatility. Between these extremes lie digital compact cameras and bridge digital cameras that "bridge" the gap between amateur and professional cameras.

Compact digital cameras

  • Compact cameras are designed to be tiny and portable and are particularly suitable for casual and "snapshot" use, thus are also called point-and-shoot cameras . Compact cameras are usually designed to be easy to use , sacrificing advanced features and picture quality for compactness and simplicity; images can usually only be stored using lossy compression ( JPEG ). Most have a built-in flash usually of low power, sufficient for nearby subjects. Live preview is almost always used to frame the photo. Most have limited motion picture capability. Compacts often have macro capability and zoom lenses but the zoom range is usually less than for bridge and DSLR cameras.

Bridge cameras

  • Bridge are higher-end digital cameras that physically and ergonomically resemble DSLRs and share with them some advanced features, but share with compacts the use of a fixed lens and a small sensor. Like compacts, most use live preview to frame the image. Their auto focus uses the same contrast-detect mechanism, but many bridge cameras have a manual focus mode, in some cases using a separate focus ring, for greater control.
  • Due to the combination of big physical size but a small sensor, many of these cameras have very highly specified lenses with large zoom range and fast aperture , partially compensating for the inability to change lenses. To compensate for the lesser sensitivity of their small sensors, these cameras almost always include an image stabilization system to enable longer handheld exposures

Digital single lens reflex cameras

  • Digital single-lens reflex cameras (DSLRs) are digital cameras based on film single-lens reflex cameras (SLRs). They take their name from their unique viewing system, in which a mirror reflects light from the lens through a separate optical viewfinder. In order to capture an image the mirror is flipped out of the way, allowing light to fall on the imager. Since no light reaches the imager during framing, auto focus is accomplished using specialized sensors in the mirror box itself. Most 21st century DSLRs also have a "live view" mode that emulates the live preview system of compact cameras, when selected.
  • These cameras have much larger sensors than the other types, typically 18 mm to 36 mm on the diagonal. This gives them superior low-light performance, less depth of field at a given aperture, and a larger size. They make use of interchangeable lenses; each major DSLR manufacturer also sells a line of lenses specifically intended to be used on their cameras. This allows the user to select a lens designed for the application at hand: wide-angle, telephoto, low-light, etc. So each lens does not require its own shutter, DSLRs use a focal-plane shutter in front of the imager, behind the mirror. The mirror flipping out of the way at the moment of exposure makes a distinctive "clack" sound.

Basic elements in photography

  1. Subject
  2. Photographer
  3. Camera
  4. Light

Lens types

  1. Normal Lens: Approximates eye view. Focal length 45 - 55 mm.
  2. Wide - Angle Lens: Greater depth of field. Shorter focal length (28mm). Includes broad scenic, larger groups of people within frame.
  3. Tele-Photo Lens: Narrower field of view than normal lens. Longer focal length (85-200mm).
    • Subject appears larger on film than normal lens. Ideal for birds, mountains, boats and distant objects.
  4.  Zoom Lens: Focal length adjustable over wide range. Good starter Zoom lenses focal length 28-85 mm. Shoots wide-angle, normal or tele-photo pictures.

View finder

  • The main purpose of the view finder is to look at the subject through it and compose the picture area before shooting it.

Picture Composition

  • Refers to arrangement or position of subjects within a photograph, so that relationship of subjects / elements effectively express a point of view.
Last modified: Saturday, 5 May 2012, 5:57 AM