1. A method for processing remotely acquired imagery, comprising: obtaining a first set of imagery data defining a first image of a panchromatic image type, said first image having a first spatial resolution; obtaining a second set of imagery data defining a second image of a multi-spectral image type, said second image having a second spatial resolution lower than said first spatial resolution; obtaining a mapping function specifying a position of pixels in said first image with respect to pixels in said second image; adapting said mapping function to a high common spatial resolution higher than said second spatial resolution; generating a third set of imagery data defining a third image of a panchromatic type based on said first set of imagery data and said adapted mapping function and having said high common spatial resolution; and adjusting said mapping function based on a first difference between said first and said third images at said high common spatial resolution.