5.exposure

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  1. 1. Aperture - Shutter Speed
  2. 2. Exposure Exposure is the total amount of light allowed to fall on the photographic medium (photographic film or image sensor) during the process of taking a photograph. Exposure value Exposure Value (EV) denotes all combinations of a camera's shutter speed and relative aperture that give the same exposure
  3. 3. Aperture An aperture is a hole or an opening through which light travels to the film or sensor
  4. 4. Shutter A shutter is a device that allows light to pass for a determined period of time, for the purpose of exposing photographic film or a light- sensitive electronic sensor to light to capture a permanent image of a scene
  5. 5. Aperture Stop The aperture stop of a photographic lens can be adjusted to control the volume of light reaching the film or image sensor.
  6. 6. If an aperture is narrow, then the admitted rays result in a sharp focus at the image plane. f/32 - narrow aperture and slow shutter speed
  7. 7. If an aperture is wide, then the admitted rays result in a sharp focus only for a certain focal length f/5.6 - wide aperture and fast shutter speed
  8. 8. Depth of Field The range of sharpness in front of and behind the subject or object focused on. The depth of field refers to the nearest and farthest points in your photograph that are in focus in your shot
  9. 9. Apertures control on DOF
  10. 10. Aperture Stop or F Stop , F ratio, Relative Aperture all denotes the Notation value The f-number (f/#) is often notated as N and is given by N = f / D f/2.8, f/3.2, f/3.5,f/4,f/4.5, f/5, f/5.6, f/6.3, f/7.1, f/8, etc.
  11. 11. The distance from a camera lens's focal point to the film/Sensor with the lens focus set to infinity. Focal Length
  12. 12. Apertures control on light The narrower the aperture, the darker the image for a given exposure time.
  13. 13. In combination with variation of shutter speed, the aperture size will regulate the film's or image sensor's degree of exposure to light.
  14. 14. Shutter Speed The duration of time for which the shutter of a camera remains open when exposing photographic film or other photosensitive material to light for the purpose of recording an image.
  15. 15. These speeds are expressed in seconds or fractions of a second. ie: 2, 1, 1/2, 1/4, 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, 1/500, 1/1000, 1/2000, 1/4000, 1/8000
  16. 16. Shutter speeds control on Light
  17. 17. B (for bulb) keeps the shutter open as long as the shutter release is held. Photo of street at night (exposure time 30 seconds)
  18. 18. T (for time) keeps the shutter open until the desired time is set. Exposure time : 3 seconds
  19. 19. Play with shutter speed Slow shutter speed combined with panning the camera can achieve a motion blur for moving objects.
  20. 20. Bubble Burst shot at 1/1000s
  21. 21. Disney ride at 1/15 s
  22. 22. (a) Fast shutter speed, short exposure of a water wave. (b) Slow shutter speed, long exposure of the wave. (a) (b)
  23. 23. Lens & Depth of Field The shorter your focal length, the more depth of field you will have. A 20mm lens will have more depth of field than a 50mm will have more than a 100mm. Much like lens strength, subject/camera distance, plays a big part in determining the possible size of depth of field. The closer you are to your focal point, or subject, the less depth of field is possible.
  24. 24. General Terminologies in DSLR DX & FX- Nikon's DX sensors measure 15.8 x 23.6 mm, while 35mm film and FX digital sensors measure 24 x 36mm. DX sensors are 1.5x smaller than 35mm film. EOS - Electro-Optical System EF Lens Electro Focus | EF S Lens - Electro-Focus Small image circle Internal Focus (IF) : smoother auto focusing and eliminates changes in lens barrel length for consistent handling. Super Integrated Coating (SIC) : lens coating that helps reduce ghost and flare to a negligible level ED (Extra-low Dispersion) is to avoid chromatic aberration ISO - International Organization for Standardization X variable amount in increase of focal length or zoom
  25. 25. Apochromat Lens Apochromat (APO) lenses have added correction for chromatic aberration.
  26. 26. UV Filter
  27. 27. Exposure Exposure is the total amount of light allowed to fall on the photographic medium (photographic film or image sensor) during the process of taking a photograph. Exposure value Exposure Value (EV) denotes all combinations of a camera's shutter speed and relative aperture that give the same exposure