Canon Powershot SD890 IS DIGITAL ELPH User Manual page 146

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When there is not enough space left on the memory card,
red-eye correction cannot be performed.
Although you can apply red-eye correction any number of
times to an image, the image quality will gradually deteriorate
with each application.
Since the correction frame will not appear automatically on
images that have already been corrected once with the Red-
Eye Correction function, use the [Add Frame] option to
correct them.