Three of the most important things to do for SEO in images is to
- Name Images correctly with a keyword in the name.
DO NOT just upload an image with the name, or number, your camera gave it – or someone else gave it. Rename the image with the right keyword for the page you are placing it on and for the topic on the page.In Google’s own words: Tell us as much as you can about the image. Give your images detailed, informative filenames. The filename can give Google clues about the subject matter of the image. Try to make your filename a good description of the subject matter of the image. For example, my-new-black-kitten.jpg is a lot more informative than IMG00023.JPG. Descriptive filenames can also be useful to users: If we’re unable to find suitable text in the page on which we found the image, we’ll use the filename as the image’s snippet in our search results.
Okay – time for a bit of technical image stuff which I will try to explain as easily as I can. It’s all about pixels, bytes and resolution. Reduce images in size so they are optimised for the area they are to occupy on your website.
To find the size of your image on your computer simply check its properties. On a PC right click on a mac Ctrl-click and go to properties then details. (or open the image up in an image programme)
An image from a camera, any camera, is made up of pixels. These are little tiny squares of colour that the image is made up of. As you can see in fig 1.
An image has a resolution and, funnily enough, resolution uses old fashioned inches and not modern centimetres.
If you are using an image for print you need it to be at least 300dpi. This is 300 dots per inch. So, for printing you need lots of dots per inch so the image is ‘tight’ and prints sharp and clear.
For the screen, however, we only need it to be 72dpi (dots per inch) it can be ‘looser’ and still display well. This means that the ‘weight’ of the image is reduced as well because it doesn’t need to be so tight and have so many pixels in that inch.