Subscribe to this blogDigital Services Lab Tech Tips #5: ABCs of Image Resolution
Posted by Chris Day on August 15, 2007
The Digital Services Lab is proud to present our fifth in a series of tips, hints, and brief tutorials for using the Macintosh and Digitization Resources in Phillips Memorial Library. To view the other Tech Tips in this series click here.
Understanding Image Resolution
Pixels, the tiny building blocks that make up digital images, can not be created: you can not take a low-resolution image pulled off of the web and change it into a high-resolution image good for printing in a magazine. This is why it is important when scanning an image, or directing a patron on how to scan an image, that you scan to the resolution that will be needed for the final output (72 dpi for the web, 300 dpi for print, 600 dpi for high quality printing).
However, there are many ways to take the information in a digital image and resize it for different purposes. For example, when you receive an email where the photo is too large to see on screen or put into a PowerPoint presentation. Here is one way to reduce the size of an image or simply adjust the dimensions of an image.
Changing the Image Size of Your Photo in Photoshop Elements
- Open Photoshop
- Open Your Original File: Go to the menu File > Open and browse to your file. (Note: You will need to know where the file is -on your desktop, flash drive, cd, etc…)
- Resize the Image: Go to the menu Image > Resize > Image Size The “Image Size” dialogue box will open. You will be able to see both the physical dimensions of your image (“Document Size”) and the “Pixel Dimensions”.
- Change the Dimensions: Make sure that the “Constrain Proprtions” check box is selected. You can now change the Height or the Width of the image and it will resize proportionally.
- Resave the Photo: If you go to the menu File and select Save As you will be able to save the file under a new name. You will then have both the original larger file and newer small file. The new file will be smaller in both file size as well as physical size.
The Digital Services Lab is located in Room 110, in the rear of the main floor of Phillips Memorial Library. We are open Mon-Thur 10am-9pm, Fri 8:30am-4:30pm, and Sun 5-9pm. Feel free to stop by if you have any questions about the Library’s Macintosh, Scanner, or other Technology Resources.
