Exposure - Factors in Digital Photography PDF

EXPOSURE Digital Photography  EXPOSURE Definition: The amount of light hitting the Sensor Factors that affect Exposure 1. Aperture 2. Shutter (Speed) 3. ISO  Factors that affect Exposure 1. Aperture (f:stop) Lens openings - open and close similar to the...

EXPOSURE Digital Photography  EXPOSURE Definition: The amount of light hitting the Sensor Factors that affect Exposure 1. Aperture 2. Shutter (Speed) 3. ISO  Factors that affect Exposure 1. Aperture (f:stop) Lens openings - open and close similar to the iris of your eye 1.Aperture (f:stop) Average 50mm lens f:1.8 to f:22 (Largest) f:1.8, f:2.8, f:4, f5.6 f:8, f:11, f:16, f:22 (Smallest) 1.Aperture (f:stop) f:1.8 (Largest lens opening, smallest f:#) f:22 (Smallest lens opening, largest f:#)  1.Aperture (f:stop) As you close down the f:stop (Make it smaller), the amount of light entering the lens is reduced by 1/2. Example - f:1.8 to f:2.8  1.Aperture (f:stop) As you open up the f:stop (Make it larger), the amount of light entering the lens is increased by 2 times. Example - f:22 to f:16  2. Shutter (Speed) The job of the shutter is to freeze or blur motion, as well as opening and closing to allow light in to expose the sensor. Fast speed – Freeze motion – 1/500 sec Slow Speed – Blur Motion - 1/100 sec Slower Speed – Blur Motion – 1/30 sec  2. Shutter (Speed) Shutter speeds on a camera can range from a 30 second exposure to 1/8000 of a second exposure time. Most cameras come with a “B” or bulb setting. Here you can keep the shutter open for as long as you want.  “B” – Bulb Setting 2 sec exposure 17 sec exposure  2. Shutter (Speed) Usual numbers on a shutter speed dial: 2, 4, 8, 15, 30, 60, 125, 250, 500, 1000. (These numbers are read as fractions) Example - 1/60 of a second 2. Shutter (Speed) Relationship to Light Increasing the shutter speed, 1/60 to 1/125 Speed Doubles (2x) Light Decreases (1/2) 2. Shutter (Speed) Relationship to Light Decreasing the shutter speed, 1/500 to 1/250 Speed Reduces (1/2) Light Increases (2x)  3. IS0 All cameras have a sensitivity rating, ISO. As the numbers increase, so does the sensitivity to light. example: 100 iso to 200 iso The speed doubles (2x), so does the sensitivity to light. Now its like doubling the amount of light hitting the sensor.  3. IS0 As the numbers decrease, so does the sensitivity to light. example: 400 iso to 200 iso The film speed is cut in half (1/2), so does the sensitivity to light. Now its like reducing the amount of light hitting the sensor. Factors that affect Exposure 1. Aperture 2. Shutter (Speed) 3. ISO QUESTIONS QUESTIONS QUESTIONS QUESTIONS QUESTIONS