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For deep zoom images we use the open source component Universal Viewer 4.10.x that comes with a dedicated accessibility statement.
Some images are available in a zoomable format with limited descriptive text-to-speech information.
The colour contrast on fonts in the Universal Viewer is below the recommended ratio.
Some links lack sufficient colour contrast with the surrounding text.
On the homepage, and some collection pages (Aero Girls, Archbishops Registers, Cause Papers), nested interactive controls may not always be announced by certain screen readers and could potentially cause focus issues for assistive technologies.
Some links on the Cause Papers collection do not have discernible text.
It is not possible to navigate and open different images for deep zoom using just a keyboard on the Universal Viewer.
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