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Photography. Is the capture of reflective light on light sensitive material. Film-Base Photography used “silver” as the light sensitive material. Digital Photography uses a light sensitive sensor made up of pixels. Digital Sensors. Two Major Types 1. CCD = Charged Coupler Device
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Photography • Is the capture of reflective light on light sensitive material. • Film-Base Photography used “silver” as the light sensitive material. • Digital Photography uses a light sensitive sensor made up of pixels.
Digital Sensors • Two Major Types • 1. CCD = Charged Coupler Device • 2. CMOS = Complementary Metal Oxide Semiconductor • Both Capture REDGREENBLUE light
Sensor Sensitivity • Is defined using the photographic term “ISO” • ISO stands for the “International Standards Organization” that sets film sensitive to light.\ • Today’s digital sensors capture all images at one set ISO but through in-camera image processing you will have the choice of many different ISO’s. • We will study the reason for using different ISO’s and their characteristics later in the semester but for now let’s focus on it’s importance in image exposure.
Exposure • Exposure = Intensity of Light (X) Time • Intensity of Light is controlled by the aperture in the camera’s lens, which is referred to as an “f/stop”. • Time is controlled by the shutter in the camera’s body, which is referred to as “shutter speeds”. • The camera’s ISO (sensitivity to light) will determined how much Intensity of Light (X) Time will be needed to make an correct Exposure
Unit Of Measurement • The unit of measurement used to measure light is called a “Stop”. • ISO’s use the measurement of a “Stop” • Lens f/stop use the measurement of a “Stop” • Shutter Speeds use the measurement of a “Stop” • Digital Camera’s most often use the following measurements: full stops, 1/2 stops, 1/3 stops
Full or 1/2 f/stops either double or half as you move from one to the other 2X - 1/2X
Full or 1/2 shutter speeds either double or half as you move from one to the other 2X - 1/2X
Full or 1/2 ISO’s either double or half as you move from one to the other 1/2X - 2X
Range of f/stops for Digital Cameras • The lowest f/stop is determined by the “speed of the lens” and will be different from camera to camera or lens to lens. • f/1, f/1.2, f/1.4, f/1.8, f/2, f/2.8 (full stops) • f/3.2, f/3.5, f/4, f/4.5, f/5.0, f5.6, f/6.3, f/7.1, f/8, f/9, f/10, f/11, f/13, f/14, f/16, f/18, f/20, f/22, f/25, f/29, f/32,………f/256 (1/3 stops)
Range of Shutter Speeds for Digital Cameras • The slowest shutter speed on any type of camera is “B” = bulb or “T” = time. Both allow you to hold open the shutter for an unlimited amount of time. • (Slowest) 1”, 0”8, 0”6, 0”5, 0”4, 0”3, 4, 5, 6, 8, 10, 13, 15, 20, 25, 30, 40, 50, 60, 80, 100, 125, 160, 200, 250, 320, 400, 500, 640, 800, 1000, 1250, 1600, 2000, 2500, 3200, 4000-(Fastest) Note: Shutter Speeds are written: 1, 1/2…..1/60……1/250
Range of ISO’s for Digital Cameras • (Less Noise) ISO 50, ISO 100, ISO 200, ISO 400, ISO 800, ISO 1600, ISO 3200, ISO H1, ISO H2(Increased Noise) • Digital Noise resembles film grain