digital photography a tool for graphic design graphic design: digital photography
TRANSCRIPT
Digital PhotographyDigital Photography
A tool for Graphic Design
Graphic Design: Digital Photography
Digital CameraDigital Camera
Graphic Design: Digital Photography
A digital camera (or digicam)
is a camera that takes video or still
photographs, or both, digitally by
recording images via an electronic
image sensor.
Graphic Design: Digital Photography
The word digitaldigital comes from the same
source as the word digit and digitus
(the Latin word for finger), as fingers are
used for discrete counting. It is most
commonly used in computing and electronics,
especially where real-world information is
converted to binary numeric form as in ditigal
audio and digital photography.
PixelPixel
Graphic Design: Digital Photography
In digital imaging, a pixelpixel, the
smallest addressable screen element
in a display device; it is the smallest
unit of picture that can be
represented or controlled.
Image SensorImage Sensor
Graphic Design: Digital Photography
An image sensor is a device that
converts an optical image into an
electronic signal. It is used
mostly in digital cameras
and other imaging devices.
Graphic Design: Digital Photography
Today, the most currently used active
pixel sensors are digital:
charge-coupled device (CCD)
OR
complementary metal–oxide–
semiconductor (CMOS).
A CCD image sensorA CCD image sensor
Graphic Design: Digital Photography
A CCD image sensor is an analog device.
When light strikes the chip it is held as a
small electrical charge in each photo sensor.
The charges are converted to voltage one
pixel at a time as they are read from the
chip. Additional circuitry in the camera
converts the voltage into digital information.
A A CMOSCMOS imaging chip imaging chip
Graphic Design: Digital Photography
A CMOS imaging chip is a type of
active pixel sensor made using the
CMOS semiconductor process. Extra
circuitry next to each photo sensor
converts the light energy to a voltage.
Additional circuitry on the chip may be
included to convert the voltage to
digital data.
Focal LengthFocal Length
Graphic Design: Digital Photography
Cameras have lenses on them to focus
incoming light and direct it towards the
image sensor at the back of the camera.
Focal lengthFocal length in a camera can be best
described as the amount of information that
makes it to the sensor relative to the distance
the subject is away from the lens.
Light ExposureLight Exposure
Graphic Design: Digital Photography
In camera terminology, light is In camera terminology, light is
measured in what are called “stops.” measured in what are called “stops.”
One stopstop represents the increment between
one doubling and the next.
Exposure ControlsExposure Controls
Graphic Design: Digital Photography
Exposure is controlled by many different things.
Two of the most important ways to control the exposure are the aperture and shutter speed.
Exposure is the amount of light that makes it to the sensor at the back of the camera.
ApertureAperture
Graphic Design: Digital Photography
To control the amount of light that makes it to the sensor, a small opening is opened and closed on top of the iris called an aperture.
Cameras let light in through an iris.
Depth of FieldDepth of Field
Graphic Design: Digital Photography
The Aperture also controls Depth of Field. Depth of Field.
Graphic Design: Digital Photography
depth of field (DOF) is the distance between the nearest and farthest objects in a scene that appear acceptably sharp in an image
Depth of FieldDepth of Field
Graphic Design: Digital Photography
Shallow Depth of FieldShallow Depth of Field
Graphic Design: Digital Photography
Large Large Depth of Depth of FieldField
Graphic Design: Digital Photography
http://www.youtube.com/watch?v=uzedefUXARE&feature=player_embedded#!
Shutter SpeedShutter Speed
Graphic Design: Digital Photography
The shutter on the front of the camera is a flap that opens and closes for small increments of time to allow light in.
Because there is limited space on the sensor for light to be absorbed, the shutter has to be very precise in how long it is open for.
Graphic Design: Digital Photography
By adjusting the shutter speed you can control the movement of your subject moving through your frame.
Shutter SpeedShutter Speed
A fast shutter speed will freeze the subject and a slow shutter speed will make it look blurred as the subject moves.
Graphic Design: Digital Photography
2000 1000 500 250 125 60 30 15 8 4 2 1 Bfast-------------------------------» slow ----------» shutter held open
These are the shutter speeds, expressed in fractions of seconds, that you will most commonly find on any semi automatic or manually operated camera.
Shutter SpeedsShutter Speeds
Graphic Design: Digital Photography