Optimizing Graphics for the Web

By Ria Mastromatteo, Educational Technology Consultant

Eight seconds. Nine seconds. Ten seconds! Seems like an instant unless you're waiting for your computer to load something. It is often said that computer users are willing to wait seven seconds for a program to load and then they move on to another site. If you want people to use your Web page, it is imperative to make sure you meet the mythical seven-second standard. You can lessen the time it takes your page to load by making the file size of your graphic images smaller.

There are five major factors in the amount of time it takes pictures to load. They are:

the dimensions of the image (the height and the width)
the type of picture (.jpg or .gif)
the number of colors
the resolution of the picture (the more dots, the more bytes, the slower the load)
the amount of compression that the picture has (this has a big impact on the speed of loading)

Of course, the question is, how do you compress your pictures into a smaller file size? You can use major graphic editors like PhotoShop or Corel. There is also a little program called Photo Crunch. You can download it off of the Web at a cost of $8 (http://Imron.com/photo.htm). You load your picture into it and then reduce the resolution until you begin to see a change in the quality of the picture. It shows your original picture and allows you to change it on the screen so that you can see how the new picture compares to the old one and allows you to lower the resolution without changing the look of the picture. Then you save it as an image for the Web in either .jpg or .bmp format/.

A rule of thumb: If you are scanning a picture, you should scan at the highest resolution possible and then optimize it and save it to the Web.