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Beginning Digital Photography
for Campus Life at Cornell
Lynn Purdon Yenkey
January 14, 2010
All photographs Copyright Lynn Purdon Yenkey

Intro & Overview
 How much camera do I need? ��(15 min)
- camera options, megapixels, & storage media��the casual
photographer needs to make quality pictures
 Upload pictures to the computer ��(3 min)
- camera cables vs. card readers
 Edit pictures to crop, remove redeye, & more (15 min)
- JPG compression (benefits and dangers)
- demo of Picasa software for basic picture editing
 Basic photography concepts (20 min)
–composition, exposure, what to think about before you click
 Q&A
 Resources

Mega what?
Mega = million / pixel = light-capturing
elements in a camera’s sensor
2048×1536 sensor elements = 3,145,728
~ 3.1 megapixels
 Defines the primary resolution of photos
At the highest image quality setting
Use camera settings to lower resolution
and save disk space

How many megapixels is enough?
What is the highest image quality you want to achieve?
What do you want to do with your photos?
 Web: use the lowest resolution: in camera or save a new version
 Personal prints / home printer quality: average quality settings
 Gift quality prints, cards, fine art: high quality
Cost: more resolution costs more, but less than it used to
 Beware of too many megapixels packed into small sensors
Memory: shooting & storage
 Get extra storage cards if you plan to shoot a lot
 Faster cards mean faster shooting & downloading (MB/s)
 Archive! External hard drives, DVDs, online storage companies

Storage Card Memory Examples
32 MB 64 MB 128 MB 256 MB 512 MB 1 GB
1 megapixel 92 180 363 730 1460 2923
2 megapixel 34 70 140 283 567 1135
3 megapixel 25 51 105 212 424 852
4 megapixel 16 32 64 128 256 512
5 megapixel 11 25 50 101 203 407
6 megapixel 10 20 40 80 160 320
7 megapixel 9 18 38 75 150 301
8 megapixel 8 16 32 64 128 256
http://www.microsoft.com/windowsxp/using/digitalphotography/expert/compactflash.mspx
These numbers may vary by camera and assume using the highest quality image setting.
How many images can you store on a memory card?
How many will you shoot in an outing?

What size print can I make?
What is your starting
resolution?
What is the output
device?
Photo lab: 240-300 ppi
Home printer—varying
resolution possibilities
Megapixels at 300 PPI at 200 PPI
2 5.8" x 3.8" 8.7" x 5.8"
3 7.1" x 4.7" 10.6" x 7.1"
4 8.2" x 5.4" 12.2" x 8.2"
5 9.1" x 6.1" 13.7" x 9.1"
6 10.0" x 6.7" 15.0" x 10.0"
8 11.5" x 7.7" 17.3" x 11.5"
12 14.1" x 9.4" 21.2" x 14.1"
16 16.3" x 10.9" 24.5" x 16.3"
22 19.1" x 12.8" 28.7" x 19.1“
http://www.cambridgeincolour.com/tutorials/digital-camera-pixel.htm

Other features to consider
Get good optics—better lenses make better photos
Optical zoom is better than digital zoom
More controls mean more control
As your skills grow, you might prefer more control
Shutter lag: the best way to miss the moment
Compare and get the least you can find (measured in
fractions of seconds)
Compensate by holding trigger half-way down to
pre-focus and set exposure readings
Battery life. Carry extras!

Uploading Images
Camera software provided
Camera is just another drive
USB cable (drains camera battery)
Digital media drives
accommodate different card sizes
Upload faster than cables

File Compression & Color Format
JPEG: benefits and risks
Small, med, large in camera
“Lossy” compression. Data is lost on each re-save.
Save a copy to edit & keep the original unchanged.
Color space:
sRBG for the Web—smallest color gamut.
Some online printers now ask for sRGB.
Adobe RGB: bigger color gamut, use for prints

Picasa Demo
http://picasa.google.com
Organize images on your computer
Share images on web albums—public and private
Edit images
Order prints
Be creative: movies, collages,
Free!

Exposure’s Basic Ingredients
ISO controls sensor’s sensitivity to light
Higher #s for low light or fast action (ISO 400 & up)
Lower #s for bright daylight, blurring, finer quality
Aperture / f - stop
Controls volume of light reaching the sensor
(like a faucet on high or low)
Controls depth of field—how much or little is in focus
Shutter speed
Controls how long light reaches the sensor
Controls appearance of movement—blurs or stops action

ISO
Controls sensor sensitivity to light
Next level up means twice as sensitive to light
High number = high light sensitivity
Enables faster shutter speeds or smaller apertures
Higher ISO adds noise (“graininess” in film)
ISO 400 typical for sports outside
ISO 1600 typical for low light
Low number = low sensitivity
Enables long shutter speeds or wider apertures
Use to intentionally blur or defocus background (DoF)
ISO 100 or 200 for bright daylight with slow-moving
subjects or stills

Aperture
How much light enters the lens opening
Moving up or down one f -stop halves or doubles the
lens opening (and the amount of light entering lens)
f /2.8, f /4, f /5.6, f /8, f /11, f /16, etc.
Inverse of shutter
speed—large aperture
(smaller number)
usually needs faster
shutter speed
“Aperture Priority”
– Av or A mode

Aperture and Depth of Field
DoF is a defining characteristic of photography
Low f - stop = more light, less DoF
High f - stop = less light, more DoF
f /2.8 ~ “wide open”:
smaller DoF (less is
in focus)
f /16: larger DoF:
2 ft to infinity in focus
Focus to create
interest
get close and zoom
or use macro

Using Depth of Field
 Small apertures (f #) shorten the area of focus, create
blurred backgrounds (“Shallow depth of field”)
 Centers attention on what is sharp.

Shutter Speed and Movement
Shutter speeds double (approx.) with each setting.
1 sec, ¼, ½, 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, 1/500, 1/1000
Inverse of aperture—
faster shutter speed
needs wider aperture
(smaller f number)
Do you want to
show movement or
stop action?
Low light needs
longer time
“Shutter Priority”
– Tv mode
Shutter speed-
based exposure

f /16 Rule
Bright daylight
Set shutter speed equal to ISO
ISO 200, then shutter is 1/200 – 1/250 sec
Aperture = f /16
Shift aperture + shutter up or down
(inversely) to get the desired setting.
For ex: 1/1000 sec @ f /8

Shutter Speed and Movement
Increase ISO to
improve stop action or
shoot in low light
Chances of blur increase
with low shutter speeds
Pre-focus where you
want to stop the action
Experiment with showing
movement or stopping it

Composition: Rule of Thirds
A rule in visual arts to
create balanced,
interesting images
Divide the image into thirds
vertically and horizontally.
Place the point of interest
at one of the red
intersections.
Place horizon lines at
thirds, not in the middle.
 Break the rule sometimes.
http://digital-photography-school.com/blog/rule-of-thirds/

Rule of Thirds
Careful composition improves even casual snapshots.

Lens Choices / Focal Length
How much do you want to show?
Wide angles
Appearance of a larger depth of field so more is in
focus
Widest angles can distort corners
Normal
Similar view to what the human eye sees
Zoom/Telephoto
Compresses the subject and background
Appearance of shorter depth of field
Hand shake is also magnified, so you tend to require
faster shutter speeds (& higher ISO)

Wide vs. Telephoto
Can you see the giraffes?

Wide Angles
Wide angles can distort what is
closest to the lens
Corner distortion, but overall effect OK

Change Your Point of View
How do you really see the scene?
What do you want the picture to
make the viewer feel ?

Be a lifelong photography student.
Think about what you want to come away with.
Get to know your camera.
Experiment—digital images are free, so
experiment & learn from mistakes.
Give self-assignments: capture blur, mood in low
light, fast action, different DoF…
try something new!
Get close to your subjects. Move around!
Have fun!

Resources
Get Prints Online
 www.mpix.com
 www.kodakgallery.com or Kodak Kiosk in stores
 www.picasa.google.com
 www.walmart.com
 http://photos.live.com
 www.flickr.com
 www.shutterfly.com
 www.snapfish.com
Camera Review Sites
 http://reviews.cnet.com/digital-camera-reviews
 http://www.bestinclass.com/digital-cameras
 http://www.dcresource.com/
 http://www.dpreview.com/reviews/compare.asp
Exposure
 http://digital-photography-school.com/blog/learning-exposure-in-digital-photography/
Megapixels
 www.digicamguides.com/learn/megapixels.html – a good description of how mega you need to get
 http://www.digicamguides.com/print/ppi-print-size.html – megapixels and printing
 http://en.wikipedia.org/wiki/Digital_camera#Image_resolution – a good description and table of different sensors and their resolutions
 http://www.digicamguides.com/learn/digital-camera-terms.html – general digital & photo terms
Shutter Lag
 These specs change, so please read latest manufacturer information.
 www.cameras.co.uk/html/shutter-lag-comparisons.cfm
 www.nytimes.com/2007/05/10/technology/10basics.html?_r=2&oref=slogin

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Beginning Digital Photography

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