[bug #63171] Strange patterns on warped images

[Pedram Ashofteh Ardakani]

Follow-up Comment #10, bug #63171 (project gnuastro):

SWarp is showing the same pattern in the JPLUS M51 image as well (comment#5)!
If you can't spot it, download the image and look more closer (it is visible,
but Warp has more pronounced intensity). Here are the steps to make these
images so you'd be able to play with it yourselves 🤩


$ wget
http://archive.cefca.es/catalogues/vo/siap/jplus-dr2/reduced/get_fits?id=771824
-Om51-single-exposure.fits.fz
$ astarithmetic m51-single-exposure.fits.fz -o m51.fits
$ astwarp m51.fits --cdelt 0.555594/3600 \
          -o m51-warp.fits --width 9245,9245 \
          --widthinpix --center 109.5309438,40.17599612
$ swarp m51.fits -SUBTRACT_BACK N \
        -PIXELSCALE_TYPE MANUAL -PIXEL_SCALE 0.555594 \
        -IMAGEOUT_NAME m51-swarp.fits -IMAGE_SIZE 9245,9245 \
        -CENTER_TYPE MANUAL -CENTER 109.5309438,40.17599612


(file #53833)

    _______________________________________________________

Additional Item Attachment:

File name: m51-jplus.jpg                  Size:369 KB
    <https://file.savannah.gnu.org/file/m51-jplus.jpg?file_id=53833>



    _______________________________________________________

Reply to this item at:

  <https://savannah.gnu.org/bugs/?63171>

_______________________________________________
Message sent via Savannah
https://savannah.gnu.org/