PyFerret saves PNG images instead of GIF, even if you specify GIF as the format. PNG format does not support animation that was present in GIF format.
At this time I would recommend creating and saving each image of the animation, and then use another program (such as ImageMagick or iMovie) to put the images together to create the animation file.
Search the Ferret archives about this topic as I think there was already quite some discussion in the last year (maybe two) about this topic (saving animations).
Karl M. Smith, Ph.D.
JISAO Univ. Wash. and PMEL NOAA
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