| About Digital Images |
| |
Resolution
Digital images are made up of hundreds of small dots called pixels. The more pixels there are per inch (ppi) the higher the resolution and the better the image quality. The Web requires a resolution of at least 72 dots per inch (dpi), but printed materials require more, for example magazine images require at least 300 dpi. The dimensions of the picture may also affect the quality of the image.
Format
Many images are stored as JPEG files (.jpg) because this format allows files to be compressed to take up less space. This is good for storage or transportation. You will also come across formats such as TIFF (Tagged Image File Format, .tif) and GIF (Graphics Interchange Format, .gif). Image software tends to allow conversion of one format to another. |
| Selecting & Evaluating Digital Images |
| It is important when selecting images for use to evaluate them along similar lines as other materials such as web sites or journal articles. |
| |
Source
Who is providing the image? Museums, art, and government or educational organizations tend to provide the most reliable images as well as some commercial sites such as those of Corbis or Getty Images. Be cautious when using images found from other types of sources; images may be copyright protected or manipulated.
Quality
Images can be enhanced or manipulated using editing software such as Adobe Photoshop. Additionally, image resolution has significant impact on the clarity and quality of the image, especially if you choose to expand the dimensions of the image. High quality resolution is 300 dpi, but 72 dpi is ideal for display on a computer monitor. Image editing software can alter color, scale, position, etc. as well as resolution and printer settings. |
| Reading images |
| |
An important aspect of finding and using images is the ability to understand and critically analyze their contents. This entails not only identifying the contents of an image, but also understanding the potential meaning(s) and impact(s) of the image.
The following links offer worksheets that can help you criticically evaluate a variety of images.
Cartoons | Maps | Motion Pictures | Photographs | Posters | All worksheets
Here are some additional resources for learning about reading images and visual literacy.
|
| Sharing & editing |
| |
Scanning
Some Libraries and campus workstations have scanners available for scanning items into digital images free of charge for UW faculty, students and staff. Locations include:
- UW Seattle
- UW Bothell & Cascadia Community College
- UW Tacoma
Editing
Editing your digital images may consist of cropping, resizing, rotating, or altering colors and contrast. Some popular programs for editing images include Adobe Illustrator, Photoshop, Image Ready, and Microsoft Paint.
Inserting images into documents
The UW Libraries have books that can help you insert images into documents in a variety of software programs. Here is a good starting point for inserting images into MS Office programs.
Emailing images
Digital images may be emailed as attachments. Techniques to do so may vary depending on your email provider. Keep in mind that you may need to resize the image to create a smaller file size; image files tend to be large files and some email providers will only allow attachments under a certain file size. Printing images
There are many factors to consider in order to optimally print an image such as printer and paper types. The following link provides a thorough overview of these factors as well as some information on advanced printing concepts: Printing Images. |
| Copyright |
| |
Copyright laws
The laws that regulate the copying and distribution of creative works are called copyright laws. When using digital images that you did not create yourself you must follow the guidelines that regulate how much you use, how you use it, where you display the work, and more (unless there is a notice that the work is free to use with no restrictions).
- The Copyright Basics page explains rights, uncopyrighted works, fair use guidelines, and more.
Student code of conduct
Become familiar with the student code of conduct. Codes of conduct almost always detail the implications of violating copyright laws.
|
| Citing |
| |
Guidelines
When using digital images that you did not create yourself, you must cite the image appropriately along with following applicable copyright regulations (above).
Here are some general guidelines for the information you should have in order to best cite an image. The exact information you use will depend on what is available or known and what is required by the source from which you get the image. Be sure to check for specific guidelines from each source you use.
- Artist's name
- Title of the image
- Institution (museum, etc.) where the image is held or owned
- Material (photograph, mixed media, watercolor, oil and canvas, digital)
- Dimensions of the work
- Date of access (when you accessed the image online)
- URL (website address where you accessed the image)
You can then format your citations according to the style you are using. Here are online guides to citation styles as well as titles and call numbers for style guides in the UW Libraries. Librarians can help with citation styles and other questions.
APA (American Psychological Association) Style
MLA (Modern Language Association of America) Style
Chicago Style
|
|
