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IRAF Tools for Mosaic image processing

Version : 4.5
Author(s) : Frank Valdes (
License : AURA
Website :

Disk space required for installation is 16.09 Mb


The MSCRED external package is used to reduce CCD mosaic data in which
the data is in the mosaic MEF data format.

The data format used by the NOAO Mosaic Data Handling Software (MDHS) is a
multiextension FITS (MEF) file. This format is produced by the the Data
Capture Agent (DCA) when observing with the NOAO Mosaic. The MEF file for
the NOAO Mosaic currently consists of nine FITS header and data units
(HDU). The first HDU, called the primary or global header unit, contains
only header information which is common to all the CCD images. The
remaining eight HDUs, called extensions, contain the images from the eight

The fact that the image data is stored as a FITS file is not significant.
Starting with IRAF V2.11, FITS files consisting of just a single primary
image may be used in the same way as any other IRAF image format. The
significant feature of the mosaic format is its multi-image structure.

With multiextension FITS files you must either use tasks which are
specifically designed to operate on these files as a unit or explicitly
specify the image within the file that is to be operated upon by general
IRAF image processing tasks. The tasks in the \fBmscred\fR package are
designed to operate on the mosaic MEF files and so you only need to specify
the filename.


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