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How do I write good alt text?
At its most basic, alt text should describe the image. However, it’s often not possible to concisely describe every element of the image, and that approach gives a ton of unnecessary information.
A better approach is to describe what the image means in the context of where it is used. Why is the image there? What information is it meant to convey to the user?
There are many contexts in which this photo could be relevant, and for each one you would want to adjust the alt text to focus on what it means in that particular context.
Here are three examples of different alt text for the same image in various contexts:
1) In an article about Indigenous art installations in Ontario:
Potential alt text: Locavore, by Indigenous artist Mary Anne Barkhouse: a sculpture installation in Carleton University’s quad that depicts a snowshoe hare and a Western coyote.
This alt text highlights the Indigeneity of the artist, the medium of art, and the location, because those are all relevant to the article’s subject.
2) In an article about representations of predator-prey relationships in art:
Potential alt text: a bronze sculpture depicting a snowshoe hare on a pedestal, observed by a Western coyote. The pedestal places the hare a short distance above the coyote.
This alt text underlines the artistic details of the sculpture, including how the animal subjects are positioned in relation to one another – details that would be relevant to this article.
3) In an article about the unveiling of the sculpture on Carleton’s campus:
Potential alt text: a gathering of Carleton community members in the quad, foregrounded by the new sculpture, Locavore.
This alt text brings the gathering in the background into focus, as the article concentrates on the event of the unveiling rather than the sculpture itself.
In each of these examples, the alt text only points out details in the image that are relevant to the overall meaning of the article. Details like the green grass and the trees in the background do not add much to any of the example articles, so they have been omitted from the alt text. Try capture the meaning of the image in a precise, clear, and concise manner.