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How to resampe image and weights to common WCS grid - Printable Version

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How to resampe image and weights to common WCS grid - bovornpratch.vijarnwannaluk - 07-18-2019 02:42

Hi everyone,

I am attempting to resample an image to the same wcs grid as another image.

In details, I have two images of the same region of the sky and same pixel scale but with different wcs footprints and psf sizes (https://imgur.com/a/FLrwX38). This includes a high-resolution image (HRI.fits, smaller psf) and a low-resolution image (LRI_x.fits, larger psf).

The software (TFIT, TPHOT) I'm using for analysis requires that the LRI and HRI be in the same wcs footprint (eg. the pixels must be aligned if one opens ds9 and does a wcs lock). Previous studies with this software mention that they used SWarp to resample the images (see this paper, section 5.1, bullet point 1). I want to use SWarp because of the speed (got a few hundred images like this) and that I also require the corresponding resampled weights.

So far, I'ver tried setting the config file CENTER value to the same CRVAL1, CRVAL2 of the HRI image. eg. CENTER 3.570245591916E+01, -4.833257803806E+00 but so far doesn't give the expected results.

SWarp version : 2.38.0
Datafiles and config (Note, they are quite large):
https://www.dropbox.com/sh/jygf9emk7vmup36/AAAuX3j3GC0ejGNhJW3oskFsa?dl=0