Fishy advice about the alt_img tag: or how to annoy the vision impaired

My Siamese fighting fish called Ian

It was an article link posted to a business Facebook group that got my goat. The writer of the article was suggesting that stuffing your website <alt_img> tags (or photo description box for those using CMS systems) with search keywords was a great way of enhancing the SEO of your site.

I would hazard a guess that the author had never sat in front of a computer, blindfolded, and relied on a screen reader to tell him what he was ‘seeing’ on the website he was visiting.

Regardless of the original reason for the invention of the tag, these days their most significant use is for people with a visual impairment who rely on screen readers to access information on the internet. Tags with no alternate text are ignored by screen readers - however to achieve this in a CMS site you must give the tag the null value of " ".

However, there seems to be a lot of misinformation out there in Google-land on the use of these tags, and in a quick random search, not a single article that I came across bothered to stress the numerous instances where the tag should be left with a null value.

General advice does tell us to leave the tag null if the image is purely decorative, but many people don’t seem to have a clear concept of the term ‘decorative’. One of the articles I came across merrily told me that if I had a picture of fluffy white clouds on my website, I should duly use the tag and write “fluffy white clouds”. Surely a picture that serves no practical purpose is ‘decorative’?

Online shops are advised to use the tag to describe the product pictured – but what if that description is already written in text below the photo?

Worked it out yet?

That’s right, your vision impaired shopper gets the information twice. Imagine a website where the product photo was actually a text graphic with a description of the product, followed by caption text which was a description of the product.

Hardly thrilling is it?

Vision Australia have partnered with a specialist digital content company who regularly publish articles offering advice on ensuring digital content is accessible for the vision impaired. A good primer article to start off with is ‘Text alternatives – some examples’. Have a read, and next time you upload an image and your CMS software prompts you for a text description, remember that leaving the field with a null value (" ") is an option.   

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