8.1.2 If convolving afterwards ¶

In case you want to convolve the image later with a given point spread function, make sure to use a larger image size. After convolution, the profiles become larger and a profile that is normally completely outside of the image might fall within it.

On one axis, if you want your final (convolved) image to be $m$ pixels and your PSF is $2n+1$ pixels wide, then when calling MakeProfiles, set the axis size to $m+2n$, not $m$. You also have to shift all the pixel positions of the profile centers on the that axis by $n$ pixels to the positive.

After convolution, you can crop the outer $n$ pixels with the section crop box specification of Crop: --section=n+1:*-n,n+1:*-n (according to the FITS standard, counting is from 1 so we use n+1) assuming your PSF is a square, see Crop section syntax. This will also remove all discrete Fourier transform artifacts (blurred sides) from the final image. To facilitate this shift, MakeProfiles has the options --xshift, --yshift and --prepforconv, see Invoking MakeProfiles.