Data Set Overview
  =================
    This data set contains images where multiple frames are mosaicked
    into a single RDR product. The methods for this process are applied
    by MIPL under OPGS, associating projections with the mosaicking
    process. It should be noted that these processes can be independent, 
    and that governing methods and software can differ between OPGS and 
    the other science instrument teams. For instance, it is possible
    that OPGS and other science teams' software will transform individual 
    images to one of the projections discussed below, without involving 
    any mosaicking. Detailed mathematical descriptions of the mosaic
    projections and algorithms will be available in a separate paper 
    'Mars Mosaic Projection Algorithms.'

    More information is found in ALEXANDERETAL2008, BOSETAL2007, and
    KELLERETAL2008.

  Processing
  ==========
    The following is a description of each mosaic:

    - Cylindrical Projection: the image is overlaid onto azimuth and
      elevation grid lines, with individual frame boundries super
      imposed and annotated by number. In this case each pixel
      represents a fixed angle in azimuth and elevation. Rows are of
      constant elevation in Mars coordinates. The horizon is level, and
      columns begin clockwise from Mars north.

    - Camera Point Perspective: a perspective projection with horizontal
      epipolar lines. The image view is as if the camera had a much
      larger field of view.

    - Cylindrical-Perspective Projection: a 360 degree view projection
      similar to the Point Perspective mosaic except that this is like a
      pinhole camera which follows the mosaic in azimuth. The horizon is
      not level in order to preserve epipolar viewing.

    - Polar Projection: concentric circles represent constant projected
      elevation. Mars nadir is at the convergent center and the horizon
      is corrected for lander tilt. North is up.

    - Vertical Projection: the creation of this type of mosaic assumes
      that the field is a plane tangent to the Martian surface with up
      pointing north. This is not an orthorectified rendering, but was
      found to be useful for rapid initial orientation.

    - Orthographic Projection: this type of mosaic is a generalization
      of the vertical projection intended primarily for use with
      Microscopic Imager data. It differs in that an arbitrary axis of
      projection (as well as X- and Y-axes in the plane of projection)
      can be specified.

    - XYZ: this mosaic contains XYZ values for each pixel in the mosaic
      rather than intensity values. The inputs to the mosaic program are
      XYZ files (or individual X, Y, or Z components), and the pixels
      are interpreted in the same way - as the coordinate of the
      corresponding pixel in Cartesian space.  Like XYZ images, they may
      consist of a single 3-band file with X, Y, and Z components, or
      separate 1 band files for each component. XYZ mosaics can be
      produced in any of the mosaic projections.  Note: these mosaics
      have a consistent coordinate system used applied to each input
      image; the output mosaic may have only one coordinate system in
      which the XYZ values are defined.

    - Surface Normal (UVW): similar in concept to XYZ mosaics, a UVW
      mosaic is simply a mosaic created from UVW (surface normal) input
      images. The pixels represent the surface normals at each point.
      Like Surface Normal (UVW) images, they can be single 3-band files
      or separate 1-band files for each component.  As with XYZ mosaics,
      any projection may be used, and all output values must be defined
      in the same coordinate system.

  Data
  ====
    1 or 3 16-bit signed integer or Float, PDS (SOAS) or dual PDS/VICAR
    (OPGS) binary file.

  Software
  ========
    The MIPL Mars Program Suite was used to generate these RDRs.

  Media/Format
  ============
    The data set will initially be delivered and kept online.  Upon
    Mission completion, the RAC Operations RDRs will be delivered to PDS 
    on DVD.

NULL