IMAGE2XY(1)

📦 version 0.98, in debian bookworm, debian trixie, fedora 43, fedora 44, ubuntu jammy, ubuntu noble, ubuntu questing, ubuntu resolute, ubuntu stonking

💖 IMAGE2XY — source extractor, but make it make sense 💖

okay so bestie, this is image2xy from the astrometry.net crew, and it's literally just a source extractor. that's the whole vibe. you feed it a FITS file, it finds the objects in there, and it hands you back a list of X, Y, FLUX. no cap. ✨

✨ SYNOPSIS ✨

image2xy [options] fitsname.fits

🌸 DESCRIPTION 🌸

You give it a FITS file, it reads it, it finds the objects, and it writes out X, Y, FLUX into fitsname.xy.fits. That's it. That's the whole thing. It's giving "small but mighty" and honestly we're obsessed. 🫶

👑 OPTIONS 👑

  • -e extension — read from a single FITS extension. one extension, one job. 💅
  • -O — overwrite the existing output file. yes, it will absolutely clobber whatever's already sitting there, so know that going in. 😭
  • -o file — write the XYlist to the filename you picked instead.
  • -L order — Lanczos order. fancy math, we love that for us. ✨
  • -8 — don't use optimization for byte (u8) images.
  • -H — downsample by a factor of 2 before running simplexy.
  • -d factor — downsample by an integer factor before running simplexy.
  • -D factor — downsample, if necessary, by this many factors of two.
  • -s scale — set the median-filter box size (default 100 pixels).
  • -w width — set the Gaussian PSF sigma (default 1 pixel).
  • -g sigma — set the image noise level.
  • -p significance — set the significance level of peaks, in sigmas (default 8 sigmas).
  • -a saddle — set the "saddle" level joining peaks, in sigmas (default 5 sigmas).
  • -P plane — pull out a single plane of a multi-color image (default: first plane).
  • -b — don't do (median-based) background subtraction.
  • -G background — subtract this 'global' background value; implies -b. bestie it literally implies -b, okay, that's the deal. 🌈
  • -m — set the maximum extended object size for deblending (default 2000 pixels).
  • -S file — save the background-subtracted image to this filename (a FITS float image).
  • -B file — save the background image to this filename.
  • -U file — save the smoothed background-subtracted image to this filename.
  • -M file — save the mask image to this filename.
  • -C file — save the connected-components image to this filename.
  • -v — verbose. repeat it for more and more verboseness. like, go off, keep stacking those -vs. 🗣️

🦋 the extension-y examples 🦋

image2xy 'file.fits[1]'

Process first extension.

image2xy 'file.fits[2]'

Process second extension.

image2xy file.fits+2

Same as above. literally the same thing, just a different spelling. iykyk. 💜

💀 AUTHOR 💀

The Astrometry.net team. Principal investigators are David W. Hogg (NYU) and Dustin Lang (CMU).

🔥 SEE ALSO 🔥

okay that's the whole page, you're all caught up, main character energy achieved. 👑

astrometry.net version 0.56 — July 2015 💖 mwah, go find some stars, bestie 🎀

📦 where this page comes from