imstar (1) - Linux Manuals


imstar - Find stars in FITS and IRAF image files


imstar [options] [FITS or IRAF filename] or [@file of image file names]



<hh:mm:ss> <dd:mm:ss> [J2000, B1950]
Coordinates for center (or reference pixel if -x is used).
-a <angle>
Image rotation angle in degrees (default 0). If multiple of 90, rotate image before search and set WCS angle to zero; if not, put in WCS.
Output B1950 (FK4) coordinates (default=image equinox)
-d <catalog name>
Read this DAOFIND style catalog of X, Y, and magnitude instead of searching for stars in the image. The format is simply white-space-separated numbers on a line, with # at the beginning of comment lines.
-e <num>
Number of pixels to ignore around image edge
Write a simple ASCII catalog file instead of tab table or DAOFIND format (number RA DEC mag ... per line, with two lines of header info)
Print heading, else do not
-i <num>
Minimum peak value for star in image (<0=-sigma) Setting this to reject all but 10-15 stars is a good way to speed up the star-finding process. If num is less than zero, the minimum peak is -num image pixel standard deviations. Setting this number rejects faint stars early in the selection process for a significant saving in computing time.
Output J2000 (FK5) coordinates (default=image equinox)
Print each star as it is found for debugging
Reflect the image left <-> right before rotating (-a) and searching for stars.
-m <magnitude>
Magnitude offset
Number of brightest stars to print
Output star list in DAOFIND format. The first three numbers on each line of the output file are X, Y, and magnitude, separated by one or more blanks or a tab. Lines beginning with # are ignored.
-p <num>
Plate scale in arcsec per pixel (default 0)
-q <c|d|o|s|x|v|+>
Output region file shape for SAOimage (default o) Characters mean: c>ross, d>iamond, s>quare, o>circle, x=X, v>ary with GSC type, +>cross.
Maximum radius for star in pixels
Sort by RA instead of flux
Output in Starbase tab table format
Verbose listing of processing intermediate results
Write output to a file in addition to standard out. If DAO format (-o), create the name by adding .dao to the image file name. If Starbase format (-t), create the name by adding .tab to the image file name. If ASCII format (-f), create the name by adding .stars to the image file name.
-x <X> <Y>
X and Y coordinates of reference pixel (if not in header or image center)
Use AIPS classic projection code (for "-SIN", "-TAN", "-ARC", "-NCP", "-GLS", "-MER", "-AIT" and "-STG" only) instead of WCSLIB proposed standard projection code.

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Jessica Mink, SAO (jmink [at]