Bring my prints and negatives and show the ones that did not develop correctly…
ASK STUDENTS: What is a photographer?
Lens: The lens allows focusing, zooming and the use of an aperture to control the amount of light. The optical qualities of the lens determine the quality of the photographs and the cost of the lens.Shutter: The shutter covers the sensor (or film in case of a film SLR). The shutter opens up when the shutter-release button is pressed to allow the light to fall on the sensor/film and create a capture. Aperture: The aperture is the opening inside the lens which allows light to pass through.Mirror: Reflects image through the viewfinder, swings out of the way when shutter is pressed so image can be captured on sensor.Pentaprism: Five-sided optical glass element that reflects light through 90°Viewfinder: Viewfinder is a slot in the camera which allows you to preview the scene.Sensor: CCD or film – captures the image
Show parts on my Rebel Xti…Basic Principle Of The CameraThe basic feature of the camera is to capture what the camera sees. When you press the shutter-release the camera makes an impression on the film (or sensor in digital cameras) to capture the data. The camera sees in terms of light reflected off the subject or the amount of light in the scene. When you point the camera towards the subject or the scene, the reflected light from the scene (or the subject) is passed through the camera lens and as soon as you release the shutter, the camera shutter opens for the fraction of time to expose the film or the camera sensor to the light to capture the impression of light and save it as analog or digital data. In the days of film cameras, a roll of photo-sensitive sheet was placed instead of the digital sensor in digital cameras.How Does The Camera Work?The light reflected off the subject enters the camera through the lens where it passes through the lens aperture. It then reaches a mirror temporarily tilted at 45 degrees which reflects the light at 90 degrees. This light then is reflected by a pentaprism glass and exits through the viewfinder where it reaches the eye of the photographer and makes it possible to preview the scene.When the photographer is ready to take the shot, the mirror (which was earlier tilted at 45 degrees) moves out of the line and the light passes straight inside. When the photographer presses the shutter release button, the shutter covering the film or the camera sensor opens up and light falls on the sensor or the film thereby forming the photographic impression. The shutter then closes after a brief delay (depending on the shutter speed setting), the mirror moves back into its previous position and the camera is ready for another shot.
Smaller the number – larger the hole – the more light alllowed inIntroduce DOF
Larger number = faster
Higher number – more sensitiveIntroduce idea of grain – DEFINEAlso referred to how fast is the film, the speed of the film.Do not confuse with shutter speed.
Auto – this is where the camera makes a best guess on a shot by shot basis. You’ll find it works in many situations but it’s worth venturing out of it for trickier lighting.Tungsten – this mode is usually symbolized with a little bulb and is for shooting indoors, especially under tungsten (incandescent) lighting (such as bulb lighting). It generally cools down the colors in photos.Fluorescent – this compensates for the ‘cool’ light of fluorescent light and will warm up your shots.Daylight/Sunny – not all cameras have this setting because it sets things as fairly ‘normal’ white balance settings.Cloudy – this setting generally warms things up a touch more than ‘daylight’ mode.Flash – the flash of a camera can be quite a cool light so in Flash WB mode you’ll find it warms up your shots a touch.Shade – the light in shade is generally cooler (bluer) than shooting in direct sunlight so this mode will warm things up a little.
You need to purchase higher capacity memory cards (4GB or more)It takes longer to transfer an image from the memory card to your computerYou need more hard drive space on your computer to store your photosYou need a more powerful computer to organize and edit your imagesYou must dramatically reduce the size of photos to send via e-mailIt takes longer to upload the original images to an online gallerySo you don’t have to buy the camera with the highest megapixel.
Introduce RAW here…
DSLR’s use a mirror that allows you to see the image you’re about to shoot through the view finder – when you take the shot the mirror flips up allowing the image sensor to capture the image.
What is Photography? Photography (noun) the process of recording images on sensitized material by the action of light, X- rays, etc, and the chemical processing of this material to produce a print, slide, or cine film
How early did photography start? 11th-16th century: The camera obscura projects an image of its surroundings on a screen Consists of a box or room with a hole in one side Light from an external scene passes through the hole and strikes a surface inside where it is reproduced, upside-down, Allows artists to hand trace the images it projected onto paper
The First PhotographsNicéphore Niépces earliest surviving photograph of a scene fromnature, circa 1826, "View from the Window at Le Gras," Saint-Loup-de-Varennes (France). Shot with a camera obscura.
"Boulevard du Temple", taken by Louis Daguerre in late 1838 or early1839, was the first-ever photograph of a person. It is an image of a busystreet, but because exposure time was over ten minutes, the city traffic wasmoving too much to appear. The exception is a man in the bottom leftcorner, who stood still getting his boots polished long enough to show up inthe picture.
Robert Cornelius, self-portrait, Oct. or Nov. 1839.The back reads, "The firstlight picture ever taken."This self-portrait is the firstphotographic portrait imageof a human ever produced.
The first permanentcolorphotograph, taken byJames Clerk Maxwellin 1861. Hephotographed atartan ribbon threetimes, throughred, green and bluefilters.
Types of Early Photographs Daguerreotype: 1839 – 1855 Ambrotype: 1854 – 1870 Tintype: 1854 – 1900 Required exposures of several minutes Expensive and each picture was a once- only affair.
Introducing Negatives A negative image is a total inversion of a positive image, in which light areas appear dark and vice versa In 1841 Henry Fox Talbot invented the negative-to- positive process Made it possible to create multiple copies of the same image
But all the variousprocesses were tediousand photography wasonly for professionals orthe very rich…
Cameras BecomeCommonplace George Eastman started a company called Kodak in the 1880s. In 1884, George Eastman invented film with a base that was flexible, unbreakable, and could be rolled. The constant changing of solid plates was no longer required.
Cameras BecomeCommonplace Eastman placed this flexible, rolled film into a self-contained box camera. The camera had a small single lens with no focusing adjustment. You’d take pictures & send the camera back to the factory to have the film, much like our disposable cameras today. This was the first camera inexpensive enough for the average person to afford.
Modern Day: 35 mm Film Basic film size Photographic film is cut into strips 35 millimeters (about 1 3/8 inches) wide— hence the name. It took until the late 1940s for 35mm film to become cheap enough for most people to afford
Modern Day:Intro to Basic Print Processing Gelatin silver print: 1895 – current Printed using negatives The dominant black-and-white photographic process of the 20th century.
In the Dark –Processing Black & White Film Process the film negatives Negatives are reverse images. Negative is placed in an enlarger that projects the image onto a photo- sensitive paper… … hence the need for it to be dark… paper is sensitive to any light except red light.
In the Dark Paper is exposed to light… The paper is put through a chemical process: Developer – starts chemical process Stop Bath – stops chemical process Fix Bath – “fixes” image onto paper
Photography Gets Colorful In B&W photographic film there is usually one layer of silver salts. Color film uses at least three layers. Dyes, which absorb to the surface of the silver salts, make the crystals sensitive to different colors.
Photography Gets Colorful In the early 1940s, commercially viable color films were brought to the market. These films used the modern technology of dye-coupled colors in which a chemical process connects the three dye layers together to create an apparent color image.
What does a camera do? The camera is a device that senses and records an image. The image can be sensed by: photographic film An electronic image sensor The image is recorded on: photographic film digital memory
What does a photographer do? Photographers control the camera and lens to "expose" the light recording material (either film or digital memory) To form/capture an image… …which, after appropriate processing (in the dark room or on your computer), is converted to a usable, printable image. Expose Capture Process
Parts of a Camera Lens Shutter Aperture Mirror Pentaprism Viewfinder Sensor
Exposure Defined The exposure of a photo determines how dark or light a photo will be when it is captured by your cameras sensor. There are three factors that affect the exposure of a photo: lens aperture shutter speed ISO
Lens Aperture Aperture is the size of the hole in the camera lens through which light enters when taking a photo.
Shutter Speed The shutter speed is the length of time that the cameras shutter is open… How long the cameras sensor is exposed to light through the lens.
ISO * With film cameras, the ISO indicates the sensitivity of the film to light With digital cameras, it specifies the light sensitivity setting for the camera. Range from 100 (low sensitivity, bright light) 3200 (high sensitivity, low light) * ISO stands for International Standards Organization, and it is a standardized industry scale for measuring sensitivity to light.
White Balance A camera setting that adjusts for lighting in order to make white objects appear white in photos. Why? Because light cast from different sources is different in color (called temperature). That is to say, light is rarely truly white in nature but our eyes adjusts. Image data acquired by sensors – either film or electronic image sensors – does not match the sensors in the human eye & does not adjust.
White Balance Auto / AWB – Your camera makes its best guess. Daylight/Sunny Cloudy Shade Tungsten – Incandescent lighting such as lights bulbs. Fluorescent Flash
White Balance The left half shows the photo as it came from the digital camera or SOOC. * The right half shows the photo adjusted.* SOOC = ―Straight Out of Camera‖
The Digital Revolution Digital cameras use an electronic image sensor based on light-sensitive electronics called CCD or CMOS. Digital image is stored electronically In 1991, Kodak produced the first digital camera advanced enough to be used successfully by professionals.
Megapixels A pixel is one dot of information in a digital photograph. A megapixel (MP or Mpx) = one million pixel Expresses the number of image sensor elements of digital cameras
Megapixels The higher the number of megapixels a digital camera can record the more information recorded the larger the image the larger the print but also… the larger the file
JPEG * JPEG is a compressed image file format. JPEG images are not limited to a certain amount of color, like GIF images are. Therefore, the JPEG format is best for compressing photographic images. The JPEG format though, due to its compression, does lose some quality. * JPEG =Joint Photographic Experts Group which created the standard.
Point & Shoot vs. DSLR DSLR have removable lenses have a reflex mirror which allows live optical viewing through the lens taking the image. Point & Shoot more compact you are not seeing a ―live‖ image there is no mirror in the camera
Film vs. Digital Convenience Flexibility in editing Cost Archiving So why does film still survive?
AssignmentBring examples of photographsyou find interesting.