Optimize your images for search engines:
- Keywords in alt text, text around the image, image name, page title;
- Preferred image formatting – jpg;
- Separate SE accessible image folder;
- Image freshness. (SEW suggests re-uploading your images to keep them fresh);
- Enabled image search option at Google webmaster tool.
- Reasonable image file size (see the discussion at WW)
- Limited number of images per page;
- Popular and reliable photo sharing hosting (e.g. Flickr is reported to help in Yahoo! image optimization).
Optimize your images for social media:
- (obvious) use really great images to give your readers another reason to spread the word;
- (to get Digg thumbnailed submission) stick to jpg format and make sure the images can be resized to (or already are) 160×120 or 160×160 pixels (Unless you have an image that can be resized that way Digg will not offer the submitter a thumbnail to go with the post).
Optimize your images for people:
- People pay more attention to a clear image where they can see details (choose high quality images).
- (Clean, clear) faces in an image get more eye fixation. (don’t use abstract images too often).
- Keep them relevant: images are not the first thing a visitor sees on a web page but they can compel him to stay (according to the eye-tracking research web text is prior to images; when looking at a printed article people see images first; with web page they see text first – nevertheless images make the visitor stay and remember the page via relevant associations).