Opening An Image File, Ajusting The Appearance Of Your Image, Resize Your Image, Applying Filters, Undo Through Stepping Backwards, Cropping Your Image, Saving Your Final Image For The Web, How Do I Create Thumbnails For My Web Pages, Imaging Tips, Image File Types ...

To open your image file. Select the File pull-down menu, then select Open. You can then use the file window to search for the location where your file is stored. The File > Open window is depicted in Figure 2. When you open your file it will appear in its own window within Photoshop. The title bar on the image window will show the name of your file and display the scale at which your image is being viewed. Any percentage number less than 100 means that you image is being shown smaller than its real size. In Figure 3 below, the picture of Seattle (seattle.tif) is being shown 46.7% of its actual size. You can use options on the View pull-down menu to zoom in and out.

In making these adjustments you can click and hold the sliders and move them left or right, or you can directly input a number in the small boxes above each slider. Make sure the Preview box is checked. This will insure that as you make an adjustment, the image you have open will show the change. Once you are satisfied with the adjustments, select OK. The dialogue box will close and the changes will be applied to your image.

Once you have made all the adjustments you want to your image (including color adjust- ments, brightness, contrast, image size, and crops) you will want to output it in a format that is appropriate for display on the Web. In other words, you need to save your image in the proper file format.

humbnail images are simply smaller versions of an image often used as a hyperlink on a Web page. They have a number of advantages: you can fit many small thumbnail images on a web page without dramatically increasing download times, they allow the viewer to get a good idea of what an image is before they download it, they can be used as a hyperlink to directly link a viewer to a larger version of a file.
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Source: www.jcsu.edu