Fixing Images

Best practices for providing alternative descriptions for images

IMPORTANT: If you intend to export your course content for use at another institution, you should fix alternative descriptions (alt-text) for images on the page where the image appears, rather than in the Files area or the Ally Dashboard area of your course. 

  

This is because when you use Ally to fix the image description in the Files or Ally Dashboard area, Ally doesn't actually change the underlying HTML your Canvas page.  Instead, Ally stores a link to the description and presents it to your students whenever they encounter that image in your course .

This really only becomes an issue if you export your course content and take it elsewhere.  As long as the course stays on PCC's Canvas, Ally has no problem serving up the linked image descriptions when needed, even when the course is copied over a new term. However, if you use the course export tool to export your course content to a Canvas Export Package (.imscc file) and then import your course content on a different instance of Canvas, the link to Ally's stored description will be broken and you will need to go through and provide new alternative descriptions on those images.

So, we do recommend that if you use Ally to provide alternative descriptions for images, that you do so by clicking the colored Ally dial on the picture where it appears on the page.  When you do that, Ally will change the underlying HTML of the page and that fix will carry over, even if you export your content and import it elsewhere.  

See Bb Ally Help for More Information Links to an external site. on this topic. 

Other image issues

Click an issue below for an explanation of what it means and how to fix it.

The image can induce seizures

Explanation: These animated images contain flashing or contrasting lights or patterns that can lead to seizures for people that suffer from photosensitive epilepsy, which is a very serious and potentially life-threatening condition. Animated images with these characteristics can be generally unpleasant to look at, even for those not prone to seizures.

Fix: Find an alternative image. Do not use this image.

The image has text that is not part of the alternative description

Explanation: The image contains text that is not represented in the description or alternative text of the image. People with screen readers or other assistive devices rely on these descriptions to understand the image content and purpose and will not be able to read any text in the image that's not part of the description.

Fix: If this is an image acting as text (like a banner graphic), replace it with actual text. If this is a screenshot that contains text components, just make sure the alt text is descriptive enough to capture the nature of the screenshot. In such cases, this is not a problem that needs to be fixed - you just need to be smarter than the machine (Ally) at determining whether or not it is a problem.

The image has contrast issues

Explanation: The image contains text with low contrast between the text and its background. This can cause the text to be difficult to read, especially for those with low vision, poor eyesight or colour blindness.

Fix: Open the image in an image editing program like Photoshop to increase the contrast.

Tip: If you do not have a fancy image editing program, use PPT. Upload the image to a PPT slide. Under the Picture Format tab, you can adjust the contrast of the image in the Corrections dropdown menu. Right click on the image to save it as a picture. There isn't an easy way to know if the contrast has been improved enough to satisfy Ally's evaluation, but use your best judgment to do what you can.

Demo: Using PowerPoint to change Image Contrast

This work, “Fixing Images,” is a derivative of "Ally Remediation Cheatsheet Links to an external site." by SBCTC Links to an external site., used under CC BY 4.0 Links to an external site..  “Fixing Images” is licensed under CC BY 4.0 Links to an external site. by Pasadena City College.