15.7.4 Providing alternate text for images
To provide alternate text for an image in DITA, you need an <alt> tag. Instead of using a GraphAlt marker, which causes the content to become an attribute, you have to insert the text via the FrameMaker Object Attributes dialog for the anchored frame; see §31.4.2 Overriding graphics settings with FrameMaker object attributes. Mif2Go produces <alt> tags if and only if you use the FrameMaker Object Attributes dialog. Place the text in the Alternate: box under Text Attributes. Do not place the text in the Defined Attributes: box under New or Changed Attribute; if you do, the content will become the attribute, which is deprecated for DITA.
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