Documentation on imcomb

Task: imcomb
Purpose: Combine images
Categories: map combination

        IMCOMB is a MIRIAD task which combines several images into
        one. The images are weighted in the region of overlap to minimise
        the rms noise.

Key: in
        Name of the input image datasets. Several can be given.
        Wildcards are supported. At least one must be given.

Key: out
        The name of the output dataset.

Key: rms
        The rms noise levels of each of the input images. This is used in
        weighting the images when combining them (and thus minimising the
        noise level in any overlap region). Only the relative magnitude
        of the noise values are important.

        The images are weighted as 1/rms**2 -- so if you wish the images
        to have speific weights, compute them accordingly. For example
        if you wish to weight two images by the ratios 4 to 1, use
          rms = 0.5,1
        where 0.5 is 1/sqrt(4)

        The default is to use the theoretical rms of the input images found
        in the image header. If this is missing, then the last valid rms
        noise level found is used. If no values are given, and the first
        dataset does not contain the rms value in the header, equal weights
        are used for all images.

Key: options
        Extra processing options. Several values can be given, separated
        by a comma. Minimum match of names is used. Possible values are:
          nonormalise  Do not renormalise the output. Normally the output
                       is normalised to account for overlap regions.