Digital Photography DeCal

EECS98/198Spring 2010Nathan YanKellen Freeman

Digital Photography DeCal – important notes!1. Administrivia at the end of lecture

2. I tend to talk fast…– sorry! >__<

3. I tend to mumble and stutter…

– sorry! >__<

4. No such thing as a dumb question

5. Website is http://www.photodecal.org

-lectures, assignments, news!

All cameras, film or digital, work the same:Photons are projected onto a photo-sensitive plane which records the light information

How it works

How it worksBy confining light to only photons which pass through a certain point, we begin to resolve “detail”

Image process

or

History of Camera Development• Many pinhole-type cameras dating back to the 11th century• Joseph Niépce recorded the first photograph in 1826, using a

photo-sensitive silver/chalk mixture (8 hour exposure)• Development of recording mediums more responsive to light:

wet plates, dry plates• George Eastman introduces photographic film in 1885, and

debuts the “Kodak” camera in 1888 – a cheap and easy to operate camera that began to popularize cameras

• Oskar Barnack developed the Leica camera in 1925, which popularized 35mm film standard

• Ihagee introduced the first single-lens reflex (SLR) camera, Exakta, in 1933, allowing photographers to view image “through the lens”

• Auto-focus developed in the Konica C35AF in 1977

History of Digital Camera Development• Began with charged couple device (CCD) sensors that recorded to analog

media• Steve Sasson produced the first such camera for Kodak in 1975

• Solid state CCD that recorded output onto cassette tape• Resolution: 10,000 pixels, or 0.01 megapixels

• First practical use in 1984, for journalism• Canon RC-701 recorded images onto "video floppies"• During 1984 Olympics images could be transmitted via telephone lines, and

image quality (780x585, 0.4MP) was acceptable for newsprint• JPEG image compression standard introduced in 1988• First true digital camera: Fuji DS-1P debuted in 1988, recording a digitized

image file to onboard memory• First camera with live image feed to LCD: Casio QV-10 in 1995• First "professional" digital SLR camera natively designed: 2.74MP Nikon D1 in

1999• First affordable "consumer" digital SLR: 6MP Canon Digital Rebel 300D in 2003

- $1000• First electronic viewfinder, interchangeable lens (EVIL): Panasonic G1 in 2008

Input:Light «photons»

Output:Electrical

signals

The Imaging Sensor

Si

Si

Si

Si

Si

Photowell

Bucketloads of Electrons!

Many electronsVoltage: HighImplication: Many photons detected, bright exposureResult: bright image

Few electronsVoltage: LowImplication: Few photons detected, dark exposureResult: dark image

Max electronsVoltage: MaxImplication: Max photons detected, brightest exposureResult: White image

No electronsVoltage: ZeroImplication: No photons detected, darkest exposureResult: Black image

From detectors to image sensors

Bigger aperture = more light!

Aperture

Longer shutter speed (exposure time) = more light collected!

Shutter speed

Electrical signal

Accumulated charge

Amplifier Voltage

Measurement

Amplified electrical signal

ISO is a “sensitivity” – higher ISO means more signal (brightness) for the input (light) you actually get

ISO sensitivity

x010

x010

x100

x111

x111

x111

x111

x111

x000

x000

x100

x110

x100

x111

x111

x111

Use software to multiply the pixel values

2x4x8x16x

Digital Multiplication

Si

Si

Si

1010

1010

0100

Image process

or

PhotonsPhotoelectrons

Electrical signal

Accumulated charge

Dig

ital r

epre

sent

atio

n of

ele

ctric

al s

igna

l

Image file

Amplifier

Analog-to-Digital

Converter

Amplified electrical signal

Photons

Electrons

Voltage Reading

Voltage Signal

Image Brightness

Shutter speed

Aperture

Quantum efficiency

Signal Amplificatio

n

Digital Multiplicatio

n

Exposure "Stops"

Stops Exposure

Shutter speed Aperture ISO sensitivity

-4 1/16x 1/1600s f/22 ISO50-3 1/8x 1/800s f/16 ISO100-2 1/4x 1/400s f/11 ISO200-1 1/2x 1/200s f/8.0 ISO4000 1x 1/100s f/5.6 ISO800+1 2x 1/50s f/4.0 ISO1600+2 4x 1/25s f/2.8 ISO3200+3 8x 1/12s f/2.0 ISO6400+4 16x 1/6s f/1.4 ISO12800

Class Enrollment:Lecture1 unit P/NPTuesday 6-7pm in 160 Kroeber (here)98 CCN: 25320198 CCN: 25574

Grading:Score 50% (cumulative) on weekly quizzes

Photo Basics:Week 1:-Anatomy of a Digital Sensor-Conversion process of light into images-Aperture, shutter speed, ISO sensitivity in sensor model

Week 2:-Side-effects of exposure parameters-Autoexposure/metering-Controlling exposure parameters in program modes

Low-light photography:Week 3-Analyzing blur-Blur reduction technology/techniques

Week 4-Defining noise-Sources of noise-Noise vs. detail

Week 5-Noise reduction methods-Creative usage of blur

Lighting:Week 6-Why flash is usually bad-Advanced flash techniques-Flash stop-action-Direction and intensity of light

Week 7-Dynamic, tonal range limitations-Balancing detail vs. contrast

Week 8Spring Break – no class

Week 9-Expanding dynamic range-Shrinking dynamic range

Week 10-White balance-Black and white conversion

Lenses:Week 11-Focal length and angle of view-Subject distance and perspective

Week 12-Focusing-Autofocusing systems-Depth of field

Week 13-Lens characteristics-Resolving power-Diffraction-Chromatic aberrations-Distortion-Software workarounds

Optional Section Enrollment:Discussion (Optional)1 unit P/NPTuesday 5-6pm in 115 Kroeber

Grading:Complete all semi-weekly assignments

Into to Photojournalism(Optional)1 unit P/NPThursday 5-6:30pm in 251 Dwinelle

Grading:Complete all semi-weekly assignmentsComplete documentary/photostory project

To apply: check on photodecal.org later tonight (~11pm)Email (nathanyan@berkeley.edu) and I will send you linkQuestionnaire due Thursday 11:59pm, will respond with CCN by Friday