astsubtractsky(1)

NAME

SubtractSky - subtract the sky value in an image

SYNOPSIS

astsubtractsky [OPTION...] ASTRdata

DESCRIPTION

SubtractSky is part of GNU Astronomy Utilities 0.2.33-8a3b. SubtractSky Finds the sky value over a grid on the input and subtracts it from the image to give a clear and uniform output.

For more information, please run any of the following commands. They will respectively show you the `Invoking SubtractSky' subsection, the complete `SubtractSky' section, or the full GNU Astronomy Utilities manual. In particular the first contains a very complete explanation of each option.

: info astsubtractsky

: info SubtractSky

: info gnuastro

If you couldn't find your answer in the manual, you can get direct help from experienced Gnuastro users and developers. For more information, please run:

: info help-gnuastro

SubtractSky options:

: Input:

-h, --hdu=STR: Extension name or number of input data.

-H, --mhdu=STR: Mask image header name.

-k, --kernel=STR: Kernel image file name for convolution.

-M, --mask=STR: Mask image file name.

-U, --khdu=STR: Kernel image header name for convolution.

: Output:

--checkconvolution: Store convolved image in `_conv.fits' file.

--checksky: Store final sky and its STD in `_sky.fits' file.

--checkskystd: Include sky standard deviation in all checks too.

-D, --dontdelete: Don't delete output if it exists.

-K, --keepinputdir: Do not remove input's dir info for output.

-o, --output=STR: Output file or directory name.

: Mesh grid:

-a, --nch1=INT: Number of channels along first FITS axis.

-b, --nch2=INT: Number of channels along second FITS axis.

--checkmesh: Store mesh IDs in `_mesh.fits' file.

-d, --mirrordist=FLT: Distance beyond mirror point. Multiple of std.

--fullconvolution: Ignore channels in imageconvolution.

--fullinterpolation: Ignore channels in interpolation.

--fullsmooth: Ignore channels in smoothing.

--interponlyblank: Only interpolate over the blank pixels.

-L, --lastmeshfrac=INT: Fraction of last mesh area to add new.

--meshbasedcheck: Each mesh in one pixel in mesh check images.

-n, --numnearest=INT: Number of nearest neighbors to interpolate.

-Q, --minmodeq=FLT: Minimum acceptable quantile for the mode.

-s, --meshsize=INT: Size of each mesh (tile) in the grid.

-T, --smoothwidth=INT: Width of smoothing kernel (odd number).

: Statistics:

-t, --sigcliptolerance=FLT Difference in STD tolerance to halt iteration.

-u, --sigclipmultip=FLT: Multiple of standard deviation in sigma-clipping.

: Operating modes:

-?, --help: give this help list

--cite: BibTeX citation for SubtractSky.

--nolog: No log file for programs which make one.

-N, --numthreads=INT: Number of CPU threads to use.

--onlydirconf: Only read current directory configuration file.

--onlyversion=STR: Only run if the program version is this.

-P, --printparams: Print parameter values to be used and abort.

-q, --quiet: Only report errors, remain quiet about steps.

--setusrconf: Set default values for this user and abort.

-S, --setdirconf: Set default values for this directory and abort.

--usage: give a short usage message

-V, --version: print program version

Mandatory or optional arguments to long options are also mandatory or optional for any corresponding short options.

GNU Astronomy Utilities home page: http://www.gnu.org/software/gnuastro/

AUTHOR

Written by Mohammad Akhlaghi

REPORTING BUGS

Report bugs to [email protected].

COPYRIGHT