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A major requirement for FESTIVAL was for it to be able to easily produce composite images made of all the SECCHI data, from EUVI to HI2. Considering the very large total field of view covered by the SECCHI telescopes (up to 90 degrees from the Sun to the outer edge of HI2), the composites are not mere images of the solar corona, they can cover large portions of the sky. So whether you are looking at a small portion of the solar disk or at a large angle composite of HI images, you must always remember that with FESTIVAL, you are looking at a map of the sky as seen from either STEREO or SOHO. This is why you ca not overlay STEREO and SOHO data: these data are not taken from the same vantage point.