› Forums › Comets › spectroscopic cross section through C/2020 R4 ATLAS › NEOWISE
This image was taken on 12th July where I went out. But I will have some others around that date. I will check. But I think I only tried the diffraction grating on 12th until it misted up then reverted to without grating.
I can’t be sure of the orientation of the lines now, and at the time, I was puzzled by the lack of obvious spectra from some of the brightest stars (unless they were out of field).