DIY: Prepping your digital images for the Web

Follow our simple rules to select the right file formats and sizes, so that uploading your photos to the Internet will be simple and mistake free.

Remember how frustrated you were when a friend sent a link to a Web album, and it took an eternity to load the images? When it's finally up, you realised the pictures had such bad resolution that you could hardly bear a second look. Well, it's not difficult to avoid those mistakes when it's your turn to get your own digital snapshots online. Just remember the following simple rules. Take note that you can utilise any photo editing software, although we've chosen to use Adobe Photoshop to illustrate.

There's nothing more annoying then opening a Web page only to face an image that's so large, you have to use the scroll bars just to see the entire picture as shown in Figure A. As a general rule, the Web sees things in terms of pixels, not cm or inches. Also, most monitors will show an image of 640 x 480 pixels without the need to scroll.

You can either crop away any useless background material with the Crop or Trim command, which will reduce the physical size of your image without losing any image quality. Or resize with Photoshop. Note that resizing your picture in a Web site design program will not reduce the file size, only the display size.

Steps:

1. Open your image in Photoshop by choosing File > Open.
2. Locate your image file, and click the "Open" button.
3. Under the Image menu, click on Image Size.
4. Ensure the Constrain Proportions and Resample Image boxes are checked in the Image Size dialog box.
5. Under the Pixel Dimensions, replace the Width field with 640 and Height field with 480.
6. Click OK.

If you've ever looked at the Web using dialup, you'd probably have a very healthy dislike for those who make their images too big. Which is why small is good. However, we're not talking physical size here, but rather, small kilobyte size. The biggest reason to resize is memory; smaller images take less memory than large ones (see table). When reducing your file size, there are two approaches as you'll learn when you read on.

Connection	Download time
56K	14.2 seconds
Digital Subscriber Line (DSL)	0.8 seconds
Cable	0.4 seconds