How Photography Actually Works

THE SCIENCE OF PHOTOGRAPHY Photography has transformed how we conceive and communicate the world, connecting us to objects and ideas many miles and years away. Film is a thing of the past, but the fundamentals of photography are the same as the first cameras made in the 1800's. The photographic lens Light bounces off real world objects, and into the camera's photographic lens. The lens' curved surface slows the light's speed and bends it towards the center of the lens. The lens's shape and its distance from the real world The lens redirects the light's path and reflects the light as an optical image inside the camera. object determine what the optical image looks like inside the camera, and how the image is recorded. Recording the image Digital cameras use image sensors to transform the optical image into electronic signals. Millions of photocells on the sensor's surface read the reflected image, convert it into pixels, and give each pixel a digital value. The SHUTTER mechanism controls two thin blinds located in front of the image sensor. The blinds open and close to control how long the image sensor is exposed to the light. The APERTURE controls how much light passes through the camera lens and onto the image sensor. Flash memory cards store the info and make The image sensor converts the light into pixels and then into digital information-bits and bytes. ready for sharing, on- screen display or print. RESOLUTION is the amount of detail in the displayed image. High resolution means more pixels, more digital information, and better image detail. It takes about 20 million pixels or 20 megapixels to match the resolution of traditional photographic film. Refining the image Focus Clarity of the optical image; moving the lens closer or further away from the image sensor changes the light reflection angle. Focal length Distance between the lens and the optical image; controlled by lens width and magnification. Exposure Amount of light that reaches the image sensor; determines the photo's quality and appearance. There are three components to understanding exposure: Narrow (f16) - Less Light - Wide DOF - Sharp background Wide (f1.6) -More Light Aperture Size of lens opening: controls amount of light and determines depth of field. - Shallow DOF - Blurred background Shutter speed Duration of the image sensor's exposure to light. Long exposure 1-30 seconds More Light, motion blurred Depth of field (DOF) Short exposure 1/1000 second Less light, freeze motion Area in front and behind the object that appears in focus. ISO Film speed or image sensor's sensitivity to light. AUTO Low sensitivity 100 ISO (slow) More light, high quality 100 200 400 ......... 800 1600 3200 6400 High sensitivity 3200 ISO (fast) Less light, low quality +500 million +7.5 billion 27,800 photos uploaded to Instagram every minute photos added to the web everyday photos uploaded to Facebook every month More than 880 billion digital photos 2014 Photo- graphic cameras Instant cameras 1826 1948 1,000AD 1900 1988 Box hole Film Digital projection cameras cameras camera THE HUFFINGTON POST Sources: http://www.kpcb.com/insights/2013-internet-trends http://www.secgowArchivesedgardata/1326801/000119312512034517/287954ds1htm http://ivetheverge.com/yahoo-flickr-event-live-blog-nyc-may-2013//