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CAMERA TECHNOLOGY and KEY PRINCIPLES for ACHIEVING A QUALITY IMAGE. REVIEW of BASIC CAMERA TECHOLOGIES AND KEY CONCEPTS. Updated July 6, 2006. CHIPS . Pick-up device - "retina" of the camera Senses light, changes light energy into electric energy, 3 chips are better than 1
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CAMERA TECHNOLOGYand KEY PRINCIPLES forACHIEVING A QUALITY IMAGE REVIEW of BASIC CAMERA TECHOLOGIES AND KEY CONCEPTS Updated July 6, 2006
CHIPS Pick-up device - "retina" of the camera • Senses light, changes light energy into electric energy, 3 chips are better than 1 • ’Charged-coupled device' CCD, chip • Durable, permanently registered
IRIS • Metal leaves which control amount of light entering the camera • Aperture is the opening • Measured in "f-stops" 1.4 - 22 (1 stop open, doubles amount of light coming in)
IRIS • f1.4 = wide open • f16 = small opening • If smallest f-stop 1.4 = fast lens (good low light) • If smallest f-stop 4.0 = slow lens (poor low light)
AUTO IRIS • ”Auto" iris - standard setting • Camera "averages" the light reading and adjusts the iris accordingly • Causes problems with areas of high contrast or w/large dark or large light areas • High contrast ratio (dark vs. light areas in the frame)
AUTO IRIS • Sports event w/harsh shadows, people shot against dark/light background • Concert or play with extensive dark areas • Nighttime shoot
MANUAL IRIS • ”Manual iris" - optional setting • Manually set the iris so that it won't change • Goal, setting the iris to pick up your subject accurately • Image through the viewfinder is best indication of iris setting • Zebra stripes indicate overexposed areas in frame (if available on cam)
LENS • Optical Zoom lens actually lengthens, shortens w/in the lens housing • Digital zoom simulates zoom electronically • Cam samples part of the image on the chip and ‘blows up’ image • Generally creates unfavorable image - grainy, pixilated
Viewfinder • Small TV monitor mounted on camera • .5 to 1 inch TV (studio viewfinders bigger) • Adjust to be comfortable tilt up and down • Focus is separate from cam focus • Slides closer and farther from camera • Eye-piece can be adjusted or opened to allow full view of the viewfinder from a distance • Check before recording, set the contrast, brightness controls
Viewfinder • Pop-out screen increasingly common • Very helpful for framing, and to let the team see the composition of a shot • Useful for “playback” of recorded material • Enables “one-man” interviews with more control • Do NOT use fold-out screen to focus - very unreliable • Limit use in bright light (hard to see) • Drains battery more quickly
Other elements of the camera. . . Special Controls (will vary with the camera) • Manual/auto focus - typical on consumer models, can be problematic, use manual focus • Work poorly on reflective or horizontal surfaces • Low light tools • Gain control - boosts sensitivity of chip normal, amplifies the video signal, +3, +6, +9db, +18db • Use only when necessary, creates grainy pic • Some cams have a ‘low lux’ setting also
Depth of Field • Key to controlling and creating depth in video, film and still photography • By controlling several interrelated variables, shooter can manipulate depth of field to: • Add depth to a shot • Make shot more interesting • Control viewer’s eyes • Depth vs. Depth of Field - not the same • Depth - having the “appearance” of 3-dimensions in two dimensional space (width & height)
Depth of Field • Area in focus in front of camera • Variables affecting DOF: • Lens length: shorter lens = greater DOF • Aperture/iris: smaller iris = greater DOF • Light: more light = greater DOF • Shutter speed: faster speed requires more light, yields shallower DOF
Depth of Field DOF • Shallow DOF: only Greeny in focus • Open Iris, f 1.4, 2.0 • Low lighting or Neutral Density filter on cam • Faster speed requires more light, yields shallower DOF
Depth of Field DOF • Great DOF: All 3 in focus • Stopped-down iris, f-12, f-16 • Well-lit scene, no ND filter • Shutter speed: slower speed requires less light, yields a greater DOF
Depth of Field • Manipulate DOF to keep part of the frame out of focus • Make your shot composition a conscious choice • Strive for depth in your shots
Depth of Field • OTHER METHODS OF CREATING DEPTH • Rack focus • Foreground framing • Positioning of objects & characters w/in frame
Color Temperature • Light temperature measured in degrees Kelvin • Outdoor light (sunny day)= 5600o Kelvin BLUE • Typical studio/field video light = 3200o degrees Kelvin REDDISH/ORANGE • Fluorescent light is 4900o K
Color Temperature • Be aware of the light situation where you are shooting • 1) SOURCE - sun, field lights, outside/inside, color temp? • 2) DIRECTION - overhead, behind/from front? • 3) INTENSITY - strong/intense or diffuse? • Control as many variables as possible, try to use uncontrollable variables to your advantage.
White balancing the camera • Proper color temperature can be attained through adjustments to the camera (white balance settings), camera filters and lighting gels. • Color balance - tells camera what "white" looks like under existing lighting conditions.
White Balance continued • Most prosumer cameras have 4 white balance settings: • Automatic - camera automatically adjusts to the light temperature • Inside - 'light bulb” icon indicates tungsten light balance (3200K) • Outside - "sun" icon indicates outside light setting (5600K)
White Balance continued • Set it manually if at all possible Manual White Balance - • 1. set master switch to 'manual' • 2. fill screen with white surface • 3. push white balance button, when it stops blinking, camera is balanced
White Balance continued • Hold white object under existing light MAKING SURE THAT DOMINANT LIGHT SOURCE FALLS ON white object • Some cams require you to hold the button down until indicator stops blinking • Others, just push button, release, wait for "OK" signal in viewfinder
White Balance continued • Professional cameras require that the proper internal filter is selected BEFORE setting the white balance • 'Manual' is the preferred method as it guarantees proper balance
The issue of Control • Know the effect you want to achieve and attempt to control as many variables a possible • Take control of the production location • Control lighting - location, intensity, direction • Control sound - eliminate unwanted sound, enhance desired sound
Control • Purposefully decide on talent, camera and lighting location before setting up. • Control as many elements as possible • Control comes through professional preparation and communication
Video Camera Technique Creating the illusion Of 3 dimensions In a 2-D medium Updated July 10, 2006
FOCUS • Technique for focusing on a stationary object • zoom in on object/subject as far as possible find area of contrast • focus • zoom out and frame (COMPOSE) your shot ... this works for stationary objects only
FOCUS • Do not use fold-out viewfinder • Do not use auto-focus • Double check focus
Camera Moves • Make all moves as smooth and intentional as possible • Do not call attention to moves • Zoom, Dolly • Pan, Truck • Arc, Crane/Boom, Tilt
ZOOM • Lengthening and shortening the lens "in" - longer, closer "out" - shorter, farther away make sure the zoom is 'motivated,’ has purpose • Avoid the tendency to 'overzoom.' • Well-composed start and finish • Usually requires a pan and tilt with the zoom
ZOOM • Useful for far away shots where importance of image overrides concern for quality - that is, if you can live with a grainy image, use the digital zoom. • Can function as an artistic choice
ZOOM IN • Pulls the viewer into the shot, into situation • More intimate and emotional (lines on the face, tension, sweat)
ZOOM IN • Narrows the angle of view which eliminates visual information at the sides of the frame Longer lens narrows the angle of view
ZOOM IN • Longer lens yields shallower depth of field, throws the background out of focus • Good for depth - narrows the angle of view which eliminates visual information at the sides of the frame • ”Forces" audience to view fewer items in the frame
ZOOM OUT • Reveals information to the viewer that they couldn't see with the tighter shot, allows space, reveals other characters or objects in the scene • Allows more space for talent movement
ZOOM OUT • Short lens widens the angle of view
DOLLY • DOLLY - movement of entire cam toward or away from the subject • Similar to a zoom but with a different effect - keeps the same 'angle of view' throughout the camera move • ”Participant" or POV orientation as camera moves through the scene
PAN • Left/right movement of camera head on stationary cam. mount (either tripod or on the shoulder of videographer) • Suggests 'observer' role (compared to a 'truck') - action 'passes by' the camera
TRUCK • Left/right movement of entire camera • Usually mounted on a rolling platform (dolly) but may be handheld • As cam follows along-side the action, allows viewer to participate in the moving scene (Indiana Jones fighting on a moving truck, Olympic sprinters)
TILT, ARC • Tilt - up/down movement of camera head on stationary cam. mount tilt - up/down movement of camera head on stationary cam mount • Arc - left/right arching movement of camera
Basic shot descriptions • Extreme long shot (XLS, ELS ) • Cam very far away from the subject (often an "establishing" shot) • Sets overall context, shows location of action • Exterior" on drama or sitcom, blimp shot at sporting event • Long shots - dramatic, landscape, don't translate well to TV
Basic shot descriptions • Long shot (LS) • Camera far from the subject, may include all talent and props in the shot • Sets context, shows relationships • All players in a basketball game, shot from back of Letterman's studio
Basic shot descriptions • Medium shot (MS) • Fairly close, "interpersonal" distance • Shows most of a person or people • May be more specific - 2S, 3S • Shows relationships, close-enough to feel "in the action"
Basic shot descriptions • Close-up (CU) • Close shot, framed tightly, only part of subject seen • Variations: bust shot, tight shot • Emotional/intense, necessary on TV (small screen)
Basic shot descriptions • Extreme close-up ( ECU, XCU) • Very close, extreme detail • The tighter the shot, the more intense