There are several ways of acquiring images. The three modes of input that we will review are images obtained using a 35mm camera, images from a digital camera and images found on the Web. Let's begin with the old-fashioned method of using a 35mm camera. All of us are familiar with photo albums. Now rather than just taking photos and putting them in an album, we can scan in these photos and put them on our web pages or e-mail them to our friends. Scanning images is easy. The software we will be using to demonstrate the ease with which you can scan and manipulate images is Adobe Photoshop 5.0 LE. Your computer will also need the driver software for the scanner that you will be using. The driver software is usually included with the scanner. The software contains plug-ins that will be used by other software on your computer.

The skill development activities in this section include:

Scanning Images

Digital Camera Images

Existing Web Images

Links to Web Sites Containing Science Images

Scanning Images

Step 1

You will need to locate and open the Adobe Photoshop software on your hard drive or under the Apple Menu.

Step 2

Next you will place the item to be scanned on the bed of the scanner. To do this, lift the lid of the scanner and align the item with the designated markings. Place the item face down on the glass.



Step 3

Once the software is open you will go to the File menu, Import and Twain Acquire.


Step 4

The twain acquire will bring up a preview screen and/or settings screen. The appearance of the preview/settings screen may be different from those illustrated below, depending upon the type of scanner you are using. To scan in the image below, an EPSON scanner was used. After the twain acquire, the following Epson screen will appear followed by the preview/scan window.

At this point you scan select scan or you may wish to change some of the settings. To see more of the options that can be changed click the Advanced button.
When you click the Advanced button, the following window will open. The settings may need to be changed, depending upon what the purpose of the scanned image will be. The settings you might want to change are the Destination and Resolution. With this particular scanner, when you change the Destination, the Resolution will automatically change to the appropriate dpi. Click to pull down the Destination menu and you can designate whether the image will be used for a web page or if it will be printed. When you do this, notice that the Resolution changes. What dpi setting is associated with Screen/Web?

Other scanners, such as the MICROTEK scanner, require you to manually select the correct dpi. For those types of scanners, use the following guidelines:

For images to be used on a web page:

  • Resolution - 72 dpi.

For images to be printed out:

  • A 300 dpi printer - scan with a resolution of 100-120 dpi.
  • A 500-725 dpi printer - scan with a resolution of 150 dpi.
Step 5


Once the dpi has been set, click the preview button to determine how the image will look.

The following progress window will appear.

Step 6

If the preview image is satisfactory, click the scan button.

The following scan progress window will appear, followed by the scanned image.

Step 7

Once you have scanned the image, click on "File" and then "Save As" to save the scanned document. Give the photo a name for example, "lighthouse.jpg." Photos should be saved as JPEG format and drawings should be saved as GIF format.

As mentioned earlier, the preview/settings windows may appear different depending upon the type of scanner used. The following image was scanned using a MICROTEK scanner. Note, you can select the exact part of the image you wish to scan by dragging the selection border.

Once you have scanned and saved the image, you can insert the image into a web page or you can open it and do some Image Manipulations.

Digital Camera Images
Another means of acquiring images is through the use of a digital camera. There are many different types of digital cameras. Depending upon which type of camera you are using, the way in which you transfer the images from the camera to the computer may be different. Some cameras have internal non-removable storage. To get the images from this type of camera onto your computer, you will need to hook a cable from the camera to the computer. Another type of camera stores images on a floppy disk. To transfer the images to the computer, simply remove the floppy disk from the camera and insert it into the computer floppy drive and retrieve the images. There are other digital cameras that store images on various media such as compact flash cards, smart media cards and memory sticks. For information on how to transfer images from all these different types of digital cameras to the computer, click here and go to the website on Digital Camera Connectivity.
Existing Web Images

The third way to acquire images is to borrow them from another website. Not all images on the Web are free to use. Special rules apply for education because of the Fair Use Section of the Copyright Law. Images from government web sites are generally free for use, but you must still check for a copyright notice. For all others, whether you download their image or put it on your site by linking to it, you must write a letter to ask for permission. Keep the letter on file. The following link contains some helpful information on copyright as well as a sample form letter you can fill in to request permission to use an image.

Links to Web Sites Containing Science Images

The following links are for sites that contain science images:

©2000-2002 April Cleveland and Julie H. Petlick for Science Junction, NC State University.
All rights reserved.
Last updated 07/31/02

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