SLR: single lens reflex (what you see is what you get)

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1 SLR: single lens reflex (what you see is what you get)

2 The anatomy of an SLR (single lens reflex) camera: 1. Light passes through the lens and strikes the mirror (green) 2. The mirror reflects the light up to focusing screen (ground glass screen; horizontal orange line) 3. Light passes through the focusing screen and into the pentaprism (5 sided mirror; orange) 4. The pentaprism makes the image right-side up and reflects it through the viewfinder (yellow) 5. When you take a picture the mirror (green) flips up, and the shutter opens (blue) to expose the digital sensor or film (red) to light.

3 EXPOSURE: the light needed to form an image. It is controlled by: Aperture (amount of light) Shutter speed (length of time) ISO/film speed (sensitivity of sensor) 3

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5 Aperture controls the amount of light coming through the lens. Aperture = f-stop. Opening up = allowing in more light Closing down = less light. Every time you open one stop, you double the amount of light. Every one stop you close down, you cut the light in half. 4

6 Aperture controls depth-of-field Depth-of-field is the range of sharpness or focus in an image.

7 Aperture and DOF f2, f2.8, f4, f5.6, f8, f11, f16, f22 Shallow depth of field (only a little is in focus) uses a larger aperture Deep depth of field (a lot is in focus from near to far) uses a smaller opening

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10 f2 f2.8 f4 f5.6 f8 f11 f16 f22

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13 Shutter speed is the length of time light enters through the camera s shutter. B, 1, 2, 4, 8, 15, 30, 60, 125, 250, 500, 1000 slow shutter speeds fast shutter speeds B = bulb, allows you to keep shutter open for as long as you want. Important: Shoot 60 or faster. If shooting slower than 60, use a tripod.

14 Shutter speed and motion B, 1, 2, 4, 8, 15, 30, 60, 125, 250, 500, 1000 slow shutter speeds fast shutter speeds Fast shutter speed: freezes motion (such as 250, 500, 1000) Slow shutter speed: blurs motion (such as 8, 15, 30) 9

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16 Panning: using a slow shutter speed and moving the camera with the subject to blur the background

17 ISO (film speed): the sensitivity of the image sensor to light; how well the sensor detects and records light

18 These photos using different ISO settings, show how dark or bright the photo would look if the aperture and shutter speed were not adjusted. Lower ISO = less light captured / darker image. Need a bright, sunny da Higher ISO = more light captured / brighter image. Can use in low light s

19 ISO affects digital noise. Noise is unwanted, extraneous color or brightness information. Low ISO = less digital noise High ISO = more noise

20 Light Meter: measures the intensity of the light to help you determine correct exposure display on LCD display in viewfinder Your reflected light meter averages the values of light to middle grey in order to compute the correct exposure.

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22 Law of Reciprocity (equivalent exposures) Inverse relationship between aperture and shutter speed. Each full stop change in aperture or shutter speed (or ISO) either doubles the light or cuts it in half, so you can have many equivalent exposures For example, f8 at 125 = f5.6 at 250 Note: With digital photography it is better to slightly underexpose than overexpose.

23 Law of Reciprocity (equivalent exposures)

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25 Bracket: to take 3 exposures of the same scene (1 at light meter reading, 1 stop over exposed, 1 stop under exposed) For Example: -1 stop: f11 at 250 Light Meter: f8 at stop: f5.6 at 250

26 Shooting Modes: Manual You choose both aperture and shutter speed (USE THIS FOR NOW) Aperture Priority You choose aperture, camera picks the best shutter speed Shutter Priority You choose shutter speed, camera picks the best aperture Program camera chooses both aperture and shutter speed, but you have more control than in auto (white balance, etc)

27 Shooting Modes for point-n-shoot cameras: Portrait Shallow Depth of Field Landscape Deep Depth of Field Sports Fast Shutter Speed Macro For close-up shooting You may have even more, such as: Night Portrait Flash w/ slow shutter speed to allow for ambient light Beach Fill Flash to fill in shadows on face and big aperture for light Snow Same as beach Aquarium Turns off flash Self Portrait Longer Focal Length to avoid distortion of face Candle Same as Night Portrait Fireworks Medium shutter to freeze, but not under expose Foliage Adjusts color; usually more saturation Kids and Pets Quicker focus and fast shutter speed

28 Image Quality: Set camera to shoot on highest quality JPEG or RAW

29 Metering Modes Matrix, Evaluative or Multi-segment: tends to be most accurate, most sophisticated (SET CAMERA TO THIS ONE FOR NOW) Center-weighted: favors the center of the scene Spot: measures small area of light in center or scene only; good if you want to meter off a particular object/tone for more info:

30 White Balance: the color balance in a photo.the camera needs to know the light source to make the colors look correct. Set WB to auto, but if the colors don t look accurate, manually change it.

31 more info Size of memory card (4 GB card will hold more pictures than a 1 GB card) Set the correct date on your camera Manual vs. auto focus UV filter to protect lens Single shot vs. continuous shooting vs. self-timer Exposure compensation dial (used to bracket or under/over expose an image) interchangeable lenses external flash (hot shoe) tripod socket

32 Note (be careful of the following): If you use Aperture-priority or Shutterpriority instead of Manual mode, when you hold in the Av or +/- button, you will under or over expose your image. In Manual mode only, this Av or +/- button will change the aperture.

33 Histogram: displays the distribution of values in an image from black to white; view the histogram to determine quality of exposure This histogram shows an almost perfect distribution of values covering about a 4 stop dynamic range from deep shadows on the left to just short of bright highlights on the right. This fits comfortably within the approximately 5 stop dynamic range capability of most digital imaging chips.

34 Clipped Histograms Here we see the same photograph taken with exposures about three and a half stops apart. Both were at an aperture of f/9. The one on the left was shot at 1/2000 sec and the one on the right at 1/200 sec. The histogram of the one at the left is bunched up at the dark end (underexposed) and the one on the right is bunched up at the light end (overexposed).

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36 Low key image

37 High key image

38 Deleting Pictures Best way to delete ALL images off of the memory card is to reformat it. You can also erase individual images you don t want.

39 For Further Information PageQuerier.jhtml?pq-path=10468&pqlocale=en_US&_requestid=9508 (Click on Digital Camera Controls and look at the digital camera modes and picture quality settings. Explore other sections of the website on your own.)