A public domain image is defined as a photograph, clip art or vector whose copyright has expired or has never been under copyright. However, you can not assume that images found openly on the web are in the public domain. Rather, a bit of research will be needed before your can legally use an image in your class. There are several actions you can take:
Listed below are some excellent sites for finding images in the public domain
Title: Sometimes when you find an image, it has an original title. If there is one, be sure to include it in your attribution! If not, don’t worry about it.
Author: The author of an image is the individual who owns the rights to it. Sometimes, the author may be more than one individual, or it may be a company. Be sure to list the author or authors when attributing a photo, and add a link to their profile page accordingly.
Source: The source of the image is the link to where the original image exists. Don’t forget to provide a link to the photo’s origin!
License: Different photos will have different restrictions. Licenses are meant to describe these restrictions, and will tell you how photos can and can’t be used. Which license is the photo under? Be sure to include that information when you attribute!
Changes: Changes you’ve made to the photo, such as saturating, desaturating, and resizing all need to be mentioned. Keep in mind that a license will identify what photo alterations can be made, but the title of the license won’t make this clear. Even though your audience can read the information in the license to see what is entailed, it will be easier for them if you include what changes you’ve made if you mention it when you attribute.
While TASL works really well for photos and other creative works that are published under a Creative Commons License, the basic premise can also be used with other images for which the creator has granted you permission to use.
Creative Commons offers six licenses for photos and each have three readable “layers” meant for different types of audiences. There’s the legal code layer, meant for lawyers, the human readable layer for users and non-specialists, and the machine readable version for software and search engines. Before you start searching for photos through Creative Commons, there are a few things to know to make your search easier and more tailored to what you’re looking for. Learn more Creative Commons photo search tips, and get some background information on copyright.
You can use creative commons licensed materials as long as you follow the license conditions. One condition of all CC licenses is attribution. Creative Commons has an excellent Best Practices for Attribution of a Photograph page. Below are some examples taken from that page.
For More Information
If you have any doubts or questions, you can read the complete attribution requirements which are spelled out in detail in the legal code of every CC license, eg. http://creativecommons.org/licenses/by/4.0/legalcode#s3a. This chart compares the detailed requirements across all versions of CC licenses.
This is an image from a Creative Commons celebration
It has a:
An OK Attribution
"Creative Commons 10th Birthday Celebration San Francisco" by tvol, used under CC BY / Desaturated from original. NOTE: This is considered a slight alternation ot the original photograph
In general the attribution statement should be placed below or next to the image being attributed. See examples above