The right anchor text

Anchor text is another important factor in image SEO. If you decide to link to images with text, your anchor text can play a role in how your image is ranked for keywords. Use descriptive anchor text that describes the image.  For example, linking to an image using a generic term like “image” or “photo” or a file name that doesn’t use keywords doesn’t give search engines much meaningful information on what the image is about. Linking to an image with keywords is helpful to search engines as well as people visiting your site.