This document discusses digital photography and images for the web. It provides an overview of digital camera history and technology, pixel and file size considerations for web images, and common file formats like JPEG, GIF and PNG. Key recommendations include keeping the longest side of photos under 1000px for websites, using PNG for small graphics and GIF for animations, and disabling GPS metadata embedding on cameras.

1. Wikispaces.com &
Digital
Photography/Web
Images
LIS 3353 – 2/2/12

2. Administrivia
 Grading
– Working on Assignment #1
– Quiz #2 in the grade center
– Status:
• Jung is grading A2, A4 and A5A
• I am working on A1 and A3
 Today’s agenda
– Quiz
– News
– HTML questions
– Digital Photography & Web Images

3. News
 Facebook IPO – what does this
mean?
 http://www.youtube.com/watch?v=
6gmP4nk0EOE

4. HTML Questions

5. Digital Photography
 1981 – Sony created first consumer digital
camera – Sony Mavica
 Digital imaging uses an electronic image
sensor to record image as data vs.
chemicals on film
 Two types of sensors:
– CCD – charge coupled device
– CMOS sensors – complementary metal-oxide
semiconductor – type of digital circuitry

6. Digital Photography
 Pixel – single element, point, dot,
that contains color
 Depending on camera capability,
you can capture images with
millions of pixels

7. Digital Photography
32x32px

8. Digital Photography -
Terminology
 Focal length
 Aperture
 ISO
 Shutter speed
 sRGB
 EXIF data/GPS
 RAW (.CR2/.NEF)

9. Digital Photography -
Terminology
 Flickr.com
– http://www.flickr.com/photos/caseycasey
/6071041513/in/photostream
– http://www.flickr.com/photos
/63738890@N00/4797299641
– http://www.flickr.com/photos/caseycasey/68054
 Instagram
 Hipstamatic

10. Digital Photography – web
images
 Things to take into consideration
– Standard monitor size changes – to be
safe, consider the maximum space
you're working with at 1024x768px
– Images should be around 100kb,
depending on the size of the site you're
working with, under 1000px at the
widest – why?

11. Digital Photography – web
images
 JPG or JPEG – standard web image
file type, lossy compression.
 JPEG – Joint Photographic Experts
Group (like W3C but for images)
 JPG can embed ICC color profile
and other metadata (e.g., EXIF)

12. Digital Photography – web
images
 GIF – Graphics Interchange Format
 Created by CompuServe in 1987
 256 colors max
 Can also animate in short loops (link)
 Largely replaced by PNG

13. Digital Photography – web
images
 PNG – portable networks graphic –
JUST for images online, not for print
 Intended to replace GIFs
 Lossless compression (vs JPG)
 Much more flexible color-wise than
GIFs

14. Digital Photography – web
images
Tiff – 7.5k
PNG 6.5k
JPG 4.7k GIF – 4k

15. Digital Photography –
summary
 For photos online – longest side
around 7-800px, no bigger than
1000px wide
 For small web graphics, use PNG
 For animated web graphics, use GIF
 Disable GPS on your phone/camera
function