mSubimage(1) Create a cutout of a FITS image

SYNOPSIS

mSubimage [-d] [-a] [-h hdu] [-s statusfile] in.fits out.fits ra dec xsize [ysize]

mSubimage -p [-d] [-h hdu] [-s statusfile] in.fits out.fits xstartpix ystartpix xpixsize [ypixsize]

DESCRIPTION

Creates a subimage (or "cutout") of a FITS file. Note that in "normal" mode,
      all the parameters (location and size) are in degrees; in pixel (-p) mode, all of 
      them are in pixels

OPTIONS

-d
Turns on debugging.
-a
All pixels - Force retrieval of whole image (useful to extract an entire HDU)
-h hdu
Operate on the specified FITS header extension (HDU)
-s statusfile
Output and errors are sent to statusfile instead of to stdout
-p
Pixel mode - create subimage using pixel locations, instead of a location on the sky

ARGUMENTS

in.fits
Input FITS file.
out.fits
Path to output FITS file.
ra
In normal mode, RA of center of output image.
dec
In normal mode, declination of center of output image.
xstartpix
In pixel mode, pixel along the x-axis where the cutout image will begin
ystartpix
In pixel mode, pixel along the y-axis where the cutout image will begin
xsize
In normal mode, width of output image in degrees.
ysize
In normal mode, height of output image in degrees (default is equal to xsize.
xpixsize
In pixel mode, width of output image in pixels
ypixsize
In pixel mode, height of output image in pixels (default is equal to xpixsize

RESULT

[struct stat="OK", content="blank, flat or normal"]

The content keyword indicates whether all pixels where NaN (blank), all pixels were the same value (flat), or the image appears to be normal.

MESSAGES

OK
[struct stat="OK", content="blank, flat or normal"]
ERROR
HDU value (hdu) must be a non-negative integer
ERROR
Cannot open status file: statusfile
ERROR
Center RA string (string) cannot be interpreted as a real number
ERROR
Center Dec string (string) cannot be interpreted as a real number
ERROR
X size string (string) cannot be interpreted as a real number
ERROR
Y size string (string) cannot be interpreted as a real number
ERROR
Invalid 'x' size
ERROR
Invalid 'y' size
ERROR
Image file filename missing or invalid FITS
ERROR
Cannot find HDU hdu
ERROR
Output wcsinit() failed.
ERROR
Location is off image
ERROR
Region outside image
ERROR
No pixels match area.
ERROR
Can't create output file: out.fits
ERROR
FITS library error

EXAMPLES

$ mSubimage image1.fits subimage.fits 307.9 37.29 .01 .01
[struct stat="OK", content="normal"]

BUGS

The drizzle algorithm has been implemented but has not been tested in this release.

If a header template contains carriage returns (i.e., created/modified on a Windows machine), the cfitsio library will be unable to read it properly, resulting in the error: [struct stat="ERROR", status=207, msg="illegal character in keyword"]

It is best for the background correction algorithms if the area described in the header template completely encloses all of the input images in their entirety. If parts of input images are "chopped off" by the header template, the background correction will be affected. We recommend you use an expanded header for the reprojection and background modeling steps, returning to the originally desired header size for the final coaddition. The default background matching assumes that there are no non-linear background variations in the individual images (and therefore in the overlap differences). If there is any uncertainty in this regard, it is safer to turn on the "level only" background matching (the "-l" flag in mBgModel.

COPYRIGHT

2001-2015 California Institute of Technology, Pasadena, California

If your research uses Montage, please include the following acknowledgement: "This research made use of Montage. It is funded by the National Science Foundation under Grant Number ACI-1440620, and was previously funded by the National Aeronautics and Space Administration's Earth Science Technology Office, Computation Technologies Project, under Cooperative Agreement Number NCC5-626 between NASA and the California Institute of Technology."

The Montage distribution includes an adaptation of the MOPEX algorithm developed at the Spitzer Science Center.